332 REPTILES. 



Gmelin, in his edition of the Systema Natures published in 

 1788. 



Klein, in his Tentamen Erpetologia 1 755, arranged the ser- 

 pents into two classes, 1. those which have the head distinct 

 from the body, and the tail elongated ; 2. those which have the 

 head not distinct from the body, and the tail obtuse. Laurenti, 

 in 1768, in his Synopsis of Reptiles, divides them into three 

 orders, viz. Leapers, as the frogs ; Walkers^ as the lizards ; 

 and Serpents. By a strange oversight, however, it has been 

 observed that he forgot to place the Tortoises in his arrange- 

 ment. Scopoli and Gmelin followed in proposing methodical 

 arrangements ; but as these were but slight modifications of that 

 of Linnaeus, it is not necessary to notice them further. 



Lacepede's arrangement, the next to be noticed, appeared in 

 his excellent work on Oviparous Quadrupeds and Serpents, 

 published in 1790, as a continuation of Buffon's great work. 

 It differs not materially from that of Linnaeus, but is valuable 

 for the accuracy of the details and the precision of the charac- 

 ters, besides the introduction of many new genera. 



The arrangement of reptiles which has been generally adopt- 

 ed is that of Alexander Brogniart, who in 1799 proposed a 

 classification, of which the highest praise is, that it has been 

 followed by Cuvier in his Regne Animal. This naturalist 

 derived his orders from the differences of organization in the 

 principal organs, such as those of respiration and generation ; 

 and with these characters combined others which appear next 

 in importance to the exercise of the animal functions ; for 

 instance, the organs of touch, of digestion, and of locomotion. 

 The result of this comparison was the division of the class into 

 four Orders, viz. 



I. CHELONIANS. Body covered with a shield or plate. 

 II. SAURIANS. Body covered with scales. 



III. OPHIDIANS. Destitute of feet. 



IV. BATRACHIANS. Body covered with a naked skin. 



Latreille, in his Histoire Naturelle des Reptiles, making part 

 of Deterville's edition of BufFon, and in his Families Naturelles 

 du Regne Animal, (1825,) has made some slight changes in 

 the arrangement of Brogniart ; but the general principle of the 



