Thomas Carlyle - "Sartor Resartus, and On Heroes, Hero Worship, and the Heroic in History"

J. W. Powell - "Canyons of the Colorado"

Annie Besant - "London Lectures of 1907"

Percy J. Brebner - "The Brown Mask"

Annual Bibliography of Commonwealth Literature 2007
This paper argues that discourses of love in Ghanaian market literature for youth offer a view into complex negotiations of agency and empowerment. Drawing on Deborah Durham's notion of youth as "social `shifters'" and Francis Nyamnjoh's conception of the "interconnectedness" of agency, I take Ghanaian market literature as one specific case of how African literature for youth foregrounds questions of continuity and change as African societies enter into increasingly complex global relations. In this literature for youth, received notions of love, often constructed out of impressions from American pop and hip hop music, carry new notions of agency that compete with existing "domesticated" forms. Authors like Ike Tandoh and Evelyn Tay employ discourses of love to offer youth alternative avenues for empowerment in a context of socio-economic disenfranchizement. In a creative process of "straddling", this writing both reveals and reproduces the contradictions that obtain in youth configurations of agency.

Form and Function

E >> E. S. (Edward Stuart) Russell >> Form and Function




The law of parallelism applied not only to Vertebrates but also to
Invertebrates. In a short paper[134] of 1824 Serres attempted an
explanation of the nervous system of Invertebrates. Invertebrates, he
considered, lacked the cerebrospinal axis of Vertebrates, and their
nervous system was the homologue of the sympathetic system of
Vertebrates. The relation of the invertebrate to the vertebrate nervous
system being thus fixed, can the nervous system of Invertebrates be
reduced to one plan? It does not seem possible to establish a common
plan for the adult nervous systems. But apply the principle of
parallelism, which has proved so valuable within the limits of the
vertebrate series. Taking insects as the highest class, we find that
there are three stages in the development of their nervous system; in
the first the nervous system is composed of two separate strands, in the
second the strands unite round the oesophagus, in the third they unite
also behind. Now in _Bulla aperta_, stage (1) is permanent; in _Clio_,
_Doris_, _Aplysia_, _Tritonia_, _Sepia_, _Helix_, stage (2) is
permanent, and in _Unio_ stage (3). In fact, all the varieties of the
nervous system of molluscs fall into one or other of these three
classes. "It follows, then, that as regards their nervous system, the
Mollusca are more or less advanced larvae of insects" (p. 380). The law
of parallelism is here applied to single organ-systems, but in later
years Serres applied it to whole organisations also, saying that the
lower Invertebrates were permanent embryos of the higher.

In the paper of 1834, already referred to, Serres pushed his
speculations further and attempted to establish the unity of type of all
animals, Vertebrates and Invertebrates alike--a favourite pastime of the
transcendentalists. It is incontestable, he admits, that adult
Invertebrates are quite different in structure from adult Vertebrates,
"but if one regards them as what I take them to be, namely, _permanent
embryos_, and if one compares their organisation with the embryogeny of
Vertebrates, one sees the differences disappear, and from their
analogies arise a crowd of unsuspected resemblances" (_loc. cit._, p.
247).

The last point of Serres' doctrine which calls for remark is his
interpretation of abnormalities as being often comparable to grades of
structure permanent in the lower animals. Thus the double aorta which
may occur as an abnormality in man is the normal and permanent state in
reptiles. This idea, of course, he got from Etienne Geoffroy St Hilaire.
It is further developed in his "_Theorie des formations et des
deformations organiques appliquee a l'anatomie comparee des
monstruosites_ (1832), and in his final large memoir of 1860 (see below,
p. 205).

In 1816 appeared a fine piece of work by J. C. Savigny on the homologies
of the appendages in Articulates. The standpoint was that of pure
morphology. "I am convinced," he wrote, "that when a more complete
examination has been made of the mouth of insects, properly so called,
that is to say, having six legs and two antennae, it will be found that
whatever form it affects it is always essentially composed of the same
elements.... The organ remains the same, only the function is modified
or changed--such is Nature's constant plan."[135] In this the influence of
Geoffroy can be traced; but the work was very free from the
exaggerations of the transcendentalists, and many of Savigny's
homologies are accepted even to-day. The first memoir dealt with the
mouth-parts of insects; the second with the anterior appendages of
Articulates generally. Savigny shows that the mouth-parts of insects can
be reduced to the type shown in Orthoptera, where there are clearly two
mandibles, two maxillae, and a lower lip formed by the fusion of two
second maxillae. All other insects have these same mouth-parts, disposed
in the same order, however much their form may have been modified in
response to new functions. He goes on to compare the anterior set of
appendages in a long series of Articulates, in _Julus_, _Scolopendra_,
_Cancer_, _Gammarus_, _Cyamus_, _Nymphon_, _Phalangium_, _Apus_,
_Caligus_, _Limulus_, and a few others. For Crustacea he established the
homologies now accepted, of the mandibles with the mandibles of insects,
of the first and second pairs of maxillae with the parts so named in
insects, and so on. He is quite clear that the maxillipedes of Crustacea
are the homologues of the feet of Hexapoda. "Their disposition must lead
one to think that the six anterior feet of _Julus_, that is to say, all
the feet of the Hexapoda, are here transformed into jaws" (_loc. cit._,
p. 48). In _Scolopendra_ also there is a similar transformation of two
pairs of legs into auxiliary jaws. In _Gammarus_, where there is only
the first pair of maxillipedes, the other two pairs have become
"retransformed" into feet. We find him supporting his comparison of the
three anterior pairs of legs in _Julus_ to the three pairs of legs in
insects by an argument drawn from embryology; for only the first three
pairs of feet are present in _Julus_ at birth (Degeer), "an observation,
which, together with their position, should cause them to be considered
as the representatives of the six thoracic feet of Hexapoda" (p. 44).

His comparison of the Arachnid appendages with those of insects and
Crustacea is very curious. As his starting-point he takes _Cyamus_,
which has antennae (two pairs) and mouth parts (four pairs) as in many
Crustacea, and then seven pairs of legs; he compares with it _Nymphon_,
which has in all seven pairs of appendages. These appendages he
homologises with the seven pairs of legs of _Cyamus_, so that the first
appendage in _Nymphon_ corresponds to the seventh appendage of _Cyamus_.
This homology is extended to all Arachnids; their first two pairs of
appendages, however they may be modified as "false" mandibles and
"false" maxillae, really correspond to the second and third maxillipedes
in Crustacea, and to the second and third pairs of feet in insects. It
is interesting to note that he treats _Limulus_ as an Arachnid, pointing
out that there is as much difference between _Apus_ and _Limulus_ as
between _Cancer_ and _Phalangium_. He describes the "gnathobases" in
_Phalangium_ and _Limulus_. We may note that he had just an inkling of
the modern doctrine that all the appendages of Articulates consist of a
basal joint bearing an inner and an outer terminal piece, for he
observes that the "cirri" of the maxillipedes of Crustacea give the
appendage the same bifid appearance as the appendages of the abdomen and
the thoracic legs of _Mysis_ (p. 50).

V. Audouin, in his memoir, _Recherches anatomiques sur le thorax des
animaux articules_,[135] applied the principle of the unity of plan and
composition to the exoskeleton of insects, Crustaceans, and Arachnids.
His guiding ideas were, "(1) that the skeleton of articulated animals is
formed of a definite number of pieces, which are either distinct or
intimately fused with one another; (2) that in many cases, some pieces
diminish or altogether disappear, while others reach an excessive
development; (3) that the increase of one piece seems to exert on the
neighbouring pieces a kind of influence which explains all the
differences one finds between the individuals of each order, family and
genus" (Sep. copy, p. 16). Geoffroy had already stated, without proof,
that the parts of the Arthropod's skeleton, however they might change in
shape and size, remained faithful to the principle of connections, at
least at their points of insertion.[137] Audouin gave the detailed
demonstration of this by his accurate and minute determination of the
pieces of the arthropod skeleton. He recognised that the body of
Arthropods was made up of a series of similar rings, and that even the
compact head of insects consisted of fused segments. In each segment
Audouin distinguished a fixed number of hard chitinous parts, the dorsal
tergum, the ventral sternum, the lateral "flanc" of three pieces, all to
be recognised by their positions relative to one another. Many of the
names which he proposed are still in use; it was he who introduced the
terms prothorax, mesothorax, and metathorax, for the three segments of
the insect's thorax. He used Geoffroy's _Loi de balancement_ to explain
cases of correlative development, such as the relation between the size
of the front wings and the development of the mesothorax. In another
paper Audouin compared the three pieces of the dorsal skeleton of
Trilobites to the tergum and the upper part of the "flanc."[138] In a
third paper of about the same time he tried to establish the homologies
of the segments throughout the Articulate series--with less success than
Savigny.

Later on, in conjunction with Milne-Edwards, he demonstrated the unity
of composition of the nervous system in Crustacea, showing how the
concentrated system of the crab was formed by the same series of ganglia
as in the Macrura.

The entomologist Latreille also tackled the problem of the homologies of
the segments in the different classes of Arthropods (Cuvier, _loc.
cit._, p. cclxxii.). He thought he could find fifteen segments in all
Arthropods. He made the retrograde step of likening the head of insects
to a single segment. But some of his homologies showed morphological
insight, _e.g._, his comparison of the "first jaws" of Arachnids to
antennae, because they were placed above the upper lip. It was he who
first pointed out the resemblance of the leaf-like gills of Ephemerid
larvae to wings, and suggested that wings were "a sort of tracheal feet."

He made also a rather hazy and speculative contribution on Okenian lines
to the problem of the relation of Arthropods to Vertebrates, likening
the carapace of Crustacea to an enormously developed hyoid, the
appendages of the tail to the ventral and anal fins of fish. The
masticatory organs of Arthropods were jaws disjointed at their
symphysis; antennae, nostrils turned outside in.

Duges also made a comparison of Articulates with Vertebrates.[139] He did
not accept Geoffroy's vertebral theory of the Arthropod skeleton, though
he admitted that in Arthropods the dorsal surface was turned towards the
ground, basing this assumption on the position of the nervous system,
and also, curiously enough, on the inverted position of the embryo on
the lower surface of the yolk. He considered that the mandibles and
first maxillae of Arthropods were the homologues of the upper and lower
jaws of Vertebrates, adducing as confirmatory evidence the fact that in
snakes the rami are separate. The labium was the equivalent of the
hyoid, the labial palps and maxillipedes the equivalent of the "hyoid"
elements which form the branchial arches.

But Duges' main contribution to morphological method was his conception
of the living organism as a colony of lesser units, which were
themselves real "organisms." "By _organism_ the author means a complex
of organs which taken together suffice to constitute, ideally or
actually, a complete animal. An 'organism' is, as it were, an elementary
or simple animal; several organisms combined form a complex animal" (p.
255). Duges hit upon this principle, which was first suggested to him by
A. Moquin-Tandon's work on the leech (1827), as a great aid in
demonstrating the unity of plan and composition throughout the animal
kingdom.[140] According to his view there are three main types of
animals--(1) Biserials, including bilaterally symmetrical animals,
composed of two parallel series of "organisms"; (2) Radiates, composed
of "organisms" arranged like the spokes of a wheel; and (3)
Raceme-animals, in which the separate "organisms" were disposed more or
less irregularly, in bunches (p. 257). The unitary "organism" is
supposed to be the same in all, only the arrangement differing. Duges of
course admitted that the centralisation of the complete organism became
greater the higher it stood in the scale, and that this held good also
in individual development. The appendages of Articulates and Vertebrates
were thought of as the members of as many separate organisms. He went so
far as to suggest that the fingers of a man's hand were the free
extremities of as many thoracic members.

Duges' conception of the organism has often been revived since in a
saner form, _e.g._, by E. Perrier, and it has a certain validity. It has
much affinity with the similar conceptions of Goethe and the German
transcendentalists.

[130] _Mem. Acad. Sci._, iv., pp. cclxxxiv.-ccci., 1824.

[131] _Ann. Sci. Nat._, xi., xii., 1827; xvi., 1829; xxi., 1830.

[132] See Radl, _loc. cit._, i., pp. 225-6.

[133] _Ann. Sci. nat._ (2), ii., p. 248, 1834.

[134] _Ann. Sci. nat._, iii., pp. 377-80, 1824.

[135] _Memoires sur les Animaux sans Vertebres_, Part I.,
p. 10, Paris, 1816.

[136] _Ann. Sci. Nat._, (1), i., pp. 97-135, 416-432,
1824.

[137] _Isis_, p. 456, 1820 (2).

[138] Cuvier, _Mem. Acad. Sci._, iv., p. cclxx., 1824.

[139] _Acad. Sci._ 18th Oct. 1831. Extract in _Ann. Sci.
Nat._, xxiv., pp. 254-60, 1831.

[140] His views were more fully elaborated in his _Memoire
sur la conformite organique dans l'echelle animale_,
Montpellier, 1832.




CHAPTER VII

THE GERMAN TRANSCENDENTALISTS


To complete our historical survey of the morphology of the early 19th
century we have now to turn back some way and consider the curious
development of morphological thought in Germany under the influence of
the _Philosophy of Nature_. We have already seen many of these notions
foreshadowed by Goethe, who had considerable affinity with the
transcendentalists, but the full development of transcendental habits of
thought comes a little later than the bulk of Goethe's scientific work,
and owes more to Kielmeyer and Oken than to Goethe himself.

A great wave of transcendentalism seems to have passed over biological
thought in the early 19th century, arising mainly in Germany, but
powerfully affecting, as we have seen, the thought of Geoffroy and his
followers. Many ideas were common to the French and German schools of
transcendental anatomy, the fundamental conception that there exists a
unique plan of structure, the idea of the scale of beings, the notion of
the parallelism between the development of the individual and the
evolution of the race. It is difficult to disentangle the part played by
each school and to determine which should have the credit for particular
theories and discoveries. The philosophy seems to have come chiefly from
Germany, the science from France. It must be borne in mind that German
comparative anatomy was largely derivative from French, that the Paris
Museum was the acknowledged anatomical centre, and that Cuvier was its
acknowledged head.

It is probably correct to say that the credit mainly belongs to the
German transcendental school for the law of the parallelism between the
stages of individual development and the stages of the scale of beings,
and the theory of the repetition or multiplication of parts within the
individual. The vertebral theory of the skull is a particular
application of the second of these generalisations.

The law of parallelism[141] seems to have been expressed first by
Kielmeyer (1793),[142] who gave to it a physiological form, saying that
the human embryo shows at first a purely vegetative life, then becomes
like the lower animals, which move but have no sensation, and finally
reaches the level of the animals that both feel and move.

The idea was next taught by Autenrieth in 1797.[143]

Oken (1779-1851) in his early tract _Die Zeugung_ (1805), and in his
_Lehrbuch der Naturphilosophie_ (1809-11) elaborated the thought, and
taught that every animal in its development passes through the classes
immediately below it. "During its development the animal passes through
all stages of the animal kingdom. The foetus is a representation of all
animal classes in time."[144] The Insect, for example, is at first Worm,
next Crab, then a perfect volant animal with limbs, a Fly (_ibid._, p.
542).

As Nature is "the representation of the individual activities of the
spirit," so the animal kingdom is the representation of the activities
or organs of man. The animal kingdom is therefore "a dismemberment of
the highest animal, _i.e._, of Man" (p. 494). Now "animals are gradually
perfected, entirely like the single animal body, by adding organ unto
organ"--the way of evolution is the way of development. Hence "animals
are only the persistent foetal stages or conditions of Man," who is the
microcosm, and contains within himself all the animal kingdom.

Oken was himself a careful student of embryology; von Baer[145] speaks of
his work (published in Oken and Kieser, _Beitraege zur vergleichenden
Zoologie, Anatomie und Physiologie_, 2 pts., 1806-7) as forming the
turning-point in our understanding of the mammalian ovum. He had
accordingly actually observed a resemblance in certain details of
structure between the human foetus and the lower animals; but the
peculiar form which the law took in his hands was a consequence of his
hazy philosophy. He saw the relation of teratological to foetal
structure, for he affirmed that "malformations are only persistent
foetal conditions" (p. 492).

The idea of comparing the embryo of higher animals with the adult of
lower was widely spread at this time among German zoologists. We find,
for example, in Tiedemann's brilliant little textbook[146] the statement
that "Every animal, before reaching its full development, passes through
the stage of organisation of one or more classes lower in the scale, or,
every animal begins its metamorphosis with the simplest organisation"
(p. 57).

Thus the higher animals begin life as a kind of fluid animal jelly which
resembles the substance of a polyp; the young mammal, like the lower
Vertebrates, has only a simple circulation, and, like them, lives in
water (the amniotic fluid); the frog is first like a worm, then develops
gills and becomes like a fish (p. 57). In his work on the anatomy of the
brain,[147] Tiedemann established the homology of the optic lobes in birds
by comparing them with foetal corpora quadrigemina in man (see Serres,
_Ann. Sci. nat._, xii., p. 112).

J. F. Meckel, in 1811, devoted a long essay to a detailed proof of the
parallelism between the embryonic states of the higher animals and the
permanent states of the lower animals. In a previous memoir in the same
collection[148] (i., 1, 1808) he had made some comparisons of this kind in
dealing with the development of the human foetus; in this memoir (ii.,
1, 1811) he brings together all the facts which seem to prove the
parallelism.

His collection of facts is a very heterogeneous one; he mingles
morphological with physiological analogies, and makes the most
far-fetched comparisons between organs belonging to animals of the most
diverse groups. He compares, for instance, the placenta with the gills
of fish, of molluscs and of worms, homologising the cotyledons with the
separate tufts of gills in _Tethys, Scyllaea_ and _Arenicola_(p. 26).
This is purely a physiological analogy. He compares the closed anus of
the early human embryo with the permanent absence of an anus in
Coelentera, and the embryo's lack of teeth with the absence of teeth in
many reptiles and fish, in birds, and in many Cetacea (p. 46).[149] These
are merely chance resemblances of no morphological importance. He
considers bladderworms as animals which have never escaped from their
amnion, and _Volvox_ as not having developed beyond the level of an egg
(p. 7). He lays much stress upon likeness of shape and of relative size,
comparing, for instance, the large multilobate liver of the human foetus
with the many-lobed liver of lower Vertebrates and of Invertebrates. In
general he shows himself, in his comparisons, lacking in morphological
insight.

His treatment of the vascular system affords perhaps the best example of
his method (pp. 8-25). The simplest form of heart is the simple tubular
organ in insects, and it is under this form that the heart first appears
in the developing chick. The bent form of the embryonic heart recalls
the heart of spiders; it lies at first free, as in the mollusc _Anomia_.
The heart consists at first of one chamber only, recalling the
one-chambered heart of Crustacea. A little later three chambers are
developed, the auricle, ventricle, and aortic bulb; at this stage there
is a resemblance to the heart of fish and amphibia. At the end of the
fourth day the auricle becomes divided into two, affording a parallel
with the adult heart of many reptiles.

In his large text-book of a somewhat later date, the _System der
vergleichenden Anatomie_ (i., 1821), he works out the idea again and
gives to it a much wider theoretic sweep, hinting that the development
of the individual is a repetition of the evolutionary history of the
race. Meckel was a timid believer in evolution. He thought it quite
possible that much of the variety of animal form was due to a process of
evolution caused by forces inherent in the organism. "The
transformations," he writes, "which have determined the most remarkable
changes in the number and development of the instruments of organisation
are incontestably much more the consequence of the tendency, inherent in
organic matter, which leads it insensibly to rise to higher states of
organisation, passing through a series of intermediate states."[150]

His final enunciation of the law of parallelism in this same volume
shows that he considered the development of the individual to be due to
the same forces that rule evolution. "The development of the individual
organism obeys the same laws as the development of the whole animal
series; that is to say, the higher animal, in its gradual evolution,
essentially passes through the permanent organic stages which lie below
it; a circumstance which allows us to assume a close analogy between the
differences which exist between the diverse stages of development, and
between each of the animal classes" (p. 514).

He was not, of course, able fully to prove his contention that the lower
animals are the embryos of the higher, and we gather from the following
passage that he could maintain it only in a somewhat modified form. "It
is certain," he writes, "that if a given organ shows in the embryo of a
higher animal a given form, identical with that shown throughout life by
an animal belonging to a lower class, the embryo, in respect of this
portion of its economy, belongs to the class in question" (p. 535). The
embryo of a Vertebrate might at a certain stage of development, be
called a mollusc, if for instance, it had the heart of a mollusc.

He admits, too, that the highest animal of all does not pass through in
his development the entire animal series. But the embryo of man always
and necessarily passes through many animal stages, at least as regards
its single organs and organ-systems, and this is enough in Meckel's eyes
to justify the law of parallelism (p. 535).

In his excellent discussion of teratology Meckel points out how the idea
of parallelism throws light upon certain abnormalities which are found
to be normal in other (lower) forms (p. 556).[151]

We may refer to one other statement of the law of parallelism--by K. G.
Carus in his _Lehrbuch der vergleichenden Anatomie_ (Leipzig, 1834). The
standpoint is again that of _Naturphilosophie_. It is a general law of
Nature, Carus thinks, that the higher formations include the lower; thus
the animal includes the vegetable, for it possesses the "vegetative" as
well as the "animal" organs. So it is, too, by a rational necessity that
the development of a perfect animal repeats the series of antecedent
formations.

As we have said, the main credit for the enunciation of the law of
parallelism belongs to the German transcendental school; but the law
owes much also to Serres, who, with Meckel, worked out its implications.
It might for convenience, and in order to distinguish it from the laws
later enunciated by von Baer and Haeckel, be called the law of
Meckel-Serres.

Under the "theory of the repetition or multiplication of parts within
the organism" may be included, first, generalisations on the serial
homology of parts, and second, more or less confused attempts to
demonstrate that the whole organisation is repeated in certain of the
parts. The recognition of serial homologies constituted a real advance
in morphology; the "philosophical" idea of the repetition of the whole
in the parts led to many absurdities. It led Oken to assert that in the
head the whole trunk is repeated, that the upper jaw corresponds to the
arms, the lower to the legs, that in each jaw the same bony divisions
exist as in the limbs, the teeth, for instance, corresponding to the
claws (_loc. cit._, p. 408). It led him to distinguish "two animals" in
every body--the cephalic and the sexual animal. Each of these has its
own organs; thus "in the perfect animal there are two intestinal systems
thoroughly distinct from each other, two intestines which belong to two
different animals, the sexual and cephalic animal, or the plant and the
animal" (p. 382). The intestine of the sexual animal is the large
intestine; the lungs of the sexual animal are the kidneys, its glottis
is the urethra, its mouth the anus. So, too, the mouth is the stomach of
the head. On another line of thought the sternum is a ventral vertebral
column. Limbs are connate ribs, the digits indicating the number of ribs
included (_cf._ Duges, _supra_, p. 88).

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