440 BATRACHIA. 



PI. glutinosus. PI persimilis. 



Limbs feeble. Limbs well developed. 



The length of the fore limb is considerably less The length of the fore limb is one-half of the 



than one-half of the distance between fore and hind distance between fore and hind limbs, 

 limbs. 



The length of the hind limb is one-half of the The length of the hind limb is considerably more 



distance between fore and hind limbs. than one-half of the distance between fore and hind 



limbs. 



The third and fourth hind toes are much shorter The length of the third and fourth hind toes 



than the cleft of the mouth. equals that of the cleft of the mouth. 



Trunk with thirteen lateral cross folds. Tnmk with twelve lateral cross folds. 



Tail subcylindrical at the base. Tail compressed at the base. 



Tongnie large, covering the whole bottom of the Tongue narrow, elliptical, not covering the whole 



mouth, its hind margin being free. width of the bottom of the mouth, without free pos- 

 terior margin. 



The series of palatine teeth is distinctly inter- The series of palatine teeth is subcontinuous. 

 rupted in the middle. 



In other respects both species are very similar, the Siamese form being black, with small, 

 scattered whitish spots. 



The only two specimens known were collected by M. Mouhot in Siam. Unfortunately no 

 mention has been made by him of the particular locality where they were obtained. They 

 are from 3 to 4 inches long. 



THE ORDER OF BURROWING BATRACHIANS— ^.^77?.^C^/.^ 



APODA. 



Body long, cylindrical, without limbs, worm-like. 



These Batrachians had been placed by early zoologists among the Snakes. A tail is absent 

 or extremely short. The skin is smooth and viscous, forming numerous annular folds ; trans- 

 verse series of rudimentary scales are imbedded in these folds, especially in those of the 

 posterior part of the body. Their eyes are rudimentary, more or less hidden below the skin. 



They constantly live below ground, burrowing like worms ; their food appears to consist 

 of mould and worms. The metamorphosis is less complete than in the two previous orders : 

 the young do not live in the water, and have quite the external appearance of the old ones, 

 but they are provided with short gills which do not project from the gill-openings. Gills 

 and gill-openings disappear at an early period, and the perfect animal has only one lung 

 developed, the other remaining rudimentary, as in most snakes. 



Only three species are known from British India ; tliey belong to two genera : — 



A small round groove in front and below the eye Epicrium, p. 441. 



A small round groove below each nostril CaecUia, p. 443. 



