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HISTORY] It is surprising that even the reptiles of his native country were most imperfectly known to the author.

With the enlargement of geographical knowledge that of reptiles was also advanced, as is sufficiently apparent from the large encyclopaedic works of Gesner, Aldrovandi and Johnston. The last-named author especially, who published the various portions of his Natural History in the middle of the 17th century, was able to embody in his

compilations notices of numerous reptiles observed by Francisco Hernandez in Mexico and by Marcgrave and Piso in Brazil. As the author had no definite idea of the Ray-Linnaean term “species,” it is not possible to give the exact number of reptiles mentioned in his work. But it may be estimated at about fifty, not including some marine fishes and fabulous creatures. He figures (or rather reproduces the figures of) about forty—some species being represented by several figures.

2. Linnaean Period: Formation of a Class Amphibia.—Within the century which succeeded these compilatory works (1650–1750) fall the labours which prepared the way for and exerted the greatest influence on Ray and Linnaeus. Although original researches in the field of herpetology were limited in extent and in number, the authors

had freed themselves from the purely literary or scholastic tendency. Men were no longer satisfied with reproducing and commenting on the writings of their predecessors; the pen was superseded by the eye, the microscope and the knife, and statements were tested by experiment. This spirit of the age manifested itself, so far as the reptiles are concerned, in Chara’s and Redi’s admirable observations on the viper, in Major’s and Vallisnieri’s detailed accounts of the anatomy of the chameleon, in the researches of Jacobaeus into the metamorphoses of the Batrachians and the structure of lizards, in Dufay’s history of the development of the salamander (for Batrachians are invariably associated with reptiles proper); in Tyson’s description of the anatomy of the rattlesnake, &c. The natural history collections formed by institutions and wealthy individuals now contained not merely skins of crocodiles or serpents stuffed and transformed into a shape to correspond with the fabulous descriptions of the ancient dragons, but, with the discovery of alcohol as a means of preserving animals, reptiles entire or dissected were exhibited for study; and no opportunity was lost of obtaining them from travellers or residents in foreign countries. Fossils also were now acknowledged to be remains of animals which had lived before the Flood, and some of them were recognized as those of reptiles.

The contributions to a positive knowledge of the animal kingdom became so numerous as to render the need of a methodical arrangement of the abundance of new facts more and more pressing. Of the two principal systematic attempts made in this period the first ranks as one of the most remarkable steps of the progress of natural history, whilst the second can only be designated as a signal failure, which ought to have been a warning to all those who in after years classified animals in what is called an, “artificial system.” As the latter attempt, originating with Klein (1685–1759), did not exercise any further influence on herpetology, it will be sufficient to have merely

mentioned it. John Ray (1628–1705) had recognized the necessity of introducing exact definitions for the several categories into which the animals had to be divided, and he maintained that these categories ought to be characterized by the structure of animals, and that all zoological knowledge had to start from the “species” as its basis. His definition of reptiles as “animalia sanguinea pulmone respirantia cor unico tantum ventriculo instructum habentia ovipara” fixed the class in a manner which was adopted by the naturalists of the succeeding hundred and fifty years. Nevertheless, Ray was not a herpetologist; his knowledge of reptiles is chiefly derived from the researches of others, from whose accounts, however, everything not based upon reliable demonstration is critically excluded. He begins with a chapter treating of frogs (Rana, with two species), toads (Bufo, with one species) and

tortoises (Testudo, with fourteen species). The second group comprises the Lacertae, twenty-five in number, and includes the salamander and newts; and the third the Serpentes, nine species, among which the limbless lizards are enumerated.

Except in so far as he made known and briefly characterized a number of reptiles, our knowledge of this class was not advanced by Linnaeus. That he associated in the 12th edition cartilaginous and other fishes with the reptiles under the name of Amphibia Nantes was the result of some misunderstanding of an observation by Garden,

and is not to be taken as a premonitory token of the recent discoveries of the relation between Batrachians and fishes. Linnaeus places reptiles, which he calls Amphibia, as the third class of the animal kingdom; he divides the genera thus:—

—Testudo (15 species); Rana (17 sp.); Draco (2 sp.); Lacerta (48 sp., including 6 Batrachians).

—Crotalus (5 species); Boa (10 sp.); Coluber (96 sp.); Anguis (15 sp.); Amphisbaena (2 sp.); Caecilia

None of the naturalists who under the direction or influence of Linnaeus visited foreign countries possessed any special knowledge of or predilection for the study of reptiles; all, however, contributed to our acquaintance with tropical forms, or transmitted well-preserved specimens to the collections at home, so that Gmelin, in the 13th edition of the Systema Naturae, was able to enumerate three hundred and seventy-one species.

The man who, with the advantage of the Linnaean method, first treated of reptiles monographically, was Laurenti. In a small book he proposed a new division of these animals, of which some ideas and terms have survived into our times, characterizing the orders, genera and species in a much more precise manner than Linnaeus, giving, for

his time, excellent descriptions and figures of the species of his native country. Laurenti might have become for herpetology what Artedi was for ichthyology, but his resources were extremely limited.

The circumstance that Chelonians are entirely omitted from his Synopsis seems due rather to the main object with which he engaged in the study of herpetology, viz. that of examining and distinguishing reptiles reputed to be poisonous, and to want of material, than to his conviction that tortoises should be relegated to another class. He divides the class into three orders:— 1., with the genera Pipa, Bufo, Rana, Hyla, and one species of “Proteus,” viz. the larva of Pseudis paradoxa.

2., the three first genera of which are Tailed Batrachians, viz. two species of Proteus (one being the P. anguinus), Triton and Salamandra; followed by true Saurians—Caudiverbera, Gecko, Chamaeleo, Iguana, Basiliscus, Draco, Cordylus, Crocodilus, Scincus, Stellio, Seps.

3., among which he continues to keep Amphisbaena, Caecilia and Anguis, but the large Linnaean genus Coluber is divided into twelve, chiefly from the scutellation of the head and form of the body. The work concludes with an account of the experiments made by Laurenti to prove the poisonous or innocuous nature of those reptiles of which he could obtain living specimens.

The next general work on reptiles is by Lacépède. It appeared in the years 1788 and 1790 under the title Histoire naturelle des quadrupèdes ovipares et des serpens (Paris, 2 vols. 4to). Although as regards treatment of details and amount of information this work far surpasses the modest attempt of Laurenti, it shows no advance towards a

more natural division and arrangement of the genera. The author depends entirely on conspicuous external characters, and classifies the reptiles into (1) oviparous quadrupeds with a tail, (2) oviparous quadrupeds without a tail, (3) oviparous