COLLECTION OF REPTILES. 



reptiles comprised in the third and last division 

 are the batracians (i). Their body is destitute 

 of scales: their form and habits are for the first 

 age, those of the fish, and their feet appear but at 

 a second period. They are divided into two 

 families, and each of these into four genera. The 

 batracians belonging to the first family have no 

 tail; they are the frogs (rana), the tree frogs 

 (hylce), the toads (bufo), and the pipas. The sala- 

 manders, the tritons, the sirens, and the proteus, 

 compose the second family. All the species be- 

 longing to the first are oviparous; the young or 

 tadpoles have no feet, live in the water, and 

 respire by means of branchice (2) ; their head is 

 very large. As they grow in size the branchice 

 become obliterated, and drop off ; the feet shoot 

 out, and the tail shortens and disappears totally. 

 We may observe here tadpoles of almost every 

 species, and in every degree of their develope- 

 ment. Their size varies according to the state 

 of metamorphosis, and according as the time at 

 which that takes place approaches the period of 

 their birth. The vital strength with w hich these 

 animals are endowed is very great, and has fur- 



(1) From the Greek batrachos, -which signifies a frog. 



(2) Branchice is the name given to the laroellated organ, situated ou 

 each side of the head of fishes, and partly exterior, by means of which 

 they separate and respire the air contained in the water.. 



