Page:EB1911 - Volume 23.djvu/155

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138
REPTILES
[HISTORY

bipeds (Chirotes and Pseudopus), (4) serpents,—an arrangement in which the old confusion of Batrachians and reptiles and the imperfect definition of lizards and snakes are continued, and which it is worthy of remark we find also adopted in Cuvier's Tableau élémentaire de l'histoire naturelle des animaux (1798), and nearly so by Latreille in his Histoire naturelle des reptiles (Paris, 1801, 4 vols. 12 mo). Lacépède's monograph, however, remained for many years deservedly the standard work on reptiles. The numerous plates with which the work is illustrated, are, for the time, well drawn, and the majority readily recognizable.

3. The Period of Elimination of Batrachians as one of the Reptilion Orders.—A new period for herpetology commences Brongniart. with Alex. Brongniart,[1] who in 1799 first recognized the characters by which Batrachians differ from the other reptiles, and by which they form a natural passage to the class of fishes. Caecilia (as also Langaha and Acrochordus) is left by Brongniart with hesitation in the order of snakes, but newts and salamanders henceforth are no more classed with lizards. He leaves the Batrachians, however, in the class of reptiles, as the fourth order. The first order comprises the Chelonians, the second the Saurians (including crocodiles and lizards), the third the Ophidians—terms which have been adopted by all succeeding naturalists. Here, however, Brongniart's merit on the classification of reptiles ends, the definition and disposition of the genera remaining much the same as in the works of his predecessors.

The activity in France in the field of natural science was at this period, in spite of the political disturbances, so great that Daudin. only a few years after Lacépède's work another, almost identical in scope and of the same extent, appeared, viz. the Histoire naturelle générale et particulière des reptiles of F. M. Daudin (Paris, 1802-3, 8 vols. 8vo). Written and illustrated with less care than that by Lacépède, it is of greater importance to the herpetologists of the present day, as it contains a considerable number of generic and specific forms described for the first time. Indeed, at the end of the work, the author states that he has examined more than eleven hundred specimens, belonging to five hundred and seventeen species, all of which he has described from nature. The system adopted is that of Brongniart, the genera are well defined, but ill arranged; it is, however, noteworthy that Caecilia takes now its place at the end of the Ophidians, and nearest to the succeeding order of Batrachians.

The next step in the development of the herpetological system was the natural arrangement of the genera. This involved a stupendous amount of labour. Although many isolated contributions were made by various workers, this task could be successfully undertaken and completed in the Paris Museum only, in which, besides Seba's and Lacépède's collections, many other herpetological treasures from other museums had been deposited by the victorious generals of the empire, and to which, through Cuvier's reputation, objects from every part of the World were attracted in a voluntary manner. The men who Duméril, Oppel and Cuvier. devoted themselves to this task were A. M. C. Duméril, Oppel and Cuvier himself. Oppel was a German who, during his visit to Paris (1807–1808), attended the lectures of Duméril and Cuvier, and at the same time studied the materials to which access was given to him by the latter in the most liberal manner. Duméril[2] maintains that Oppel's ideas and information were entirely derived from his lectures, and that Oppel himself avows this to be the case. The passage,[3] however, to which he refers is somewhat ambiguous, and it is certain that there is the greatest possible difference between the arrangement published by Duméril in 1806 (Zoologie Analytique, Paris, 8vo) and that proposed by Oppel in his Ordnungen, Familien, und Gattungen der Reptilien (Munich, 1811, 4to). There is no doubt that Oppel profited largely by the teaching of Duméril, but, on the other hand, there is sufficient internal evidence in the works of both authors, not only that Oppel worked independently, but also that Duméril and Cuvier owed much to their younger fellow-labourer, as Cuvier himself indeed acknowledges more than once.

Oppel's classification may be shortly indicated thus:—

Order 1. TESTUDINATA or CHÉLONIENS.
Fam. 1. Chelonii (gen. Mydas, Coriacea).
Fam. 2. Amydae (gen. Trionyx, Chelys, Testudo, Emys).
Order 2. SQUAMATA.
Sect. A. Saurii.
Fam. 1. Crocodilini (gen. Crocodilus, Gavialis, Alligator).
Fam. 2. Geckoides (gen. Gecko, Stellio, Agama).
Fam. 3. Iguanoides (gen. Camaeleo, Draco, Iguana, Basiliscus, Lophyrus, Anolis).
Fam. 4. Lacertini (gen. Tupinambis, Dracaena, Lacerta, Tachydromus).
Fam. 5. Scincoides (gen. Scincus, Seps, Scheltopusik, Anguis).
Fam. 6. Chalcidici (gen. Chalcides, Bimanus, Bipes, Ophisaurus).
Sect. B. Ophidii.
Fam. 1. Anguiformes (gen. Tortrix, Amphisbaena, Typhlops).
Fam. 2. Constrictores (gen. Boa, Eryx).
Fam. 3. Hydri (gen. Platurus, Hydrophis).
Fam. 4. Pseudo-viperae (gen. Acrochordus, Erpeton).
Fam. 5. Crotalini (gen. Crotalus, Trigonocephalus).
Fam. 6. Viperini (gen. Vipera, Pseudoboa).
Fam. 7. Colubrini (gen. Coluber, Bungarus).
Order 3. NUDA or BATRACII.

In this classification we notice three points, which indicate a decided progress towards a natural system. (1) The four orders proposed by Brongniart are no more considered cosubordinate in the class, but the Saurians and Ophidians are associated as sections of the same order, a view held by Aristotle but abandoned by all following naturalists. The distinction between lizards and snakes is carried out in so precise a manner that one genus only, Amphisbaena, is wrongly placed. (2) The true reptiles have now been entirely divested of all heterogeneous elements by relegating positively Caecilia to the Batrachians, a view for which Oppel had been fully prepared by Duméril, who pointed out in 1807 that “les cécilies se rapprochent considerablement des batraciens auxquels elles semblent lier l'ordre entier des serpens.”[4] (3) An attempt is made at arranging the genera into families, some of which are still retained at the present day.

In thus giving a well-merited prominence to Oppel's labours we are far from wishing to detract from the influence exercised by the master spirit of this period, Cuvier. Without his guidance Oppel probably never would have found a place among the promoters of herpetological science. But Cuvier's principal researches on reptiles were incidental or formed part of some more general plan; Oppel concentrated his on this class only. Cuvier adopts the four orders of reptiles proposed by Brongniart as equivalent elements of the class, and restores the blind-worms and allied lizards and, what is worse, also the Caecilias, to the Ophidians. The chameleons and geckos are placed in separate groups, and the mode of dividing the latter has been retained to the present day. Also a natural division of the snakes, although the foreign elements mentioned are admitted into the order, is sufficiently indicated by his arrangement of the “vrais serpens proprement dits” as (1) non-venomous snakes, (2) venomous snakes with several maxillary teeth, and (3) venomous snakes with isolated poison-fangs. He distinguishes the species of reptiles with a precision not attained in any previous work.

Cuvier's researches into the osteology of reptiles had also the object of discovering the means of understanding the fossil remains which now claimed the attention of French, English and German naturalists. Extinct Chelonian and Crocodilian

  1. Bull. Acad. Sci. (1800), Nos. 35, 36.
  2. Erpét. génér., i. p. 259.
  3. “Wäre es nicht die Ermunterung . . . dieser Freunde gewesen, so würde ich überzeugt von den Mängeln, denen eine solche Arbeit bei aller möglichen Vorsicht doch unterworfen ist, es nie gewagt haben, meine Eintheilung bekannt zu machen, obwohl selbe Herr Duméril in seinen Lectionen vom jahre 1809 schon vorgetragen, und die Thiere im Cabinet darnach bezeichnet hat” (preface, p. viii). A few lines further on he emphatically declares that the classification is based upon his own researches.
  4. Memoires de zoologie et d'anatomie comparée (Paris, 1807, 8vo), p. 45.