360 REPTILES. OPHIDIA. 



H. favis, Cuv. (Aipysiirus, Lacep.) With 151 large plates un- 

 der the body ; twenty-eight small scales under the tail ; neck 

 very broad ; thirteen plates on the head. Inhabits New Hol- 

 land. An. Mus. iv. pi. 56, fig. 3. 



H. curtus, Cuv. Body compressed ; head flattish ; colour pale yel- 

 low, with a series of decurrent dusky bands, somewhat confluent 

 above. About a foot long. Inhabits India. Shaw, iii. 562. 



H. spiralu, Cuv. Body much compressed, the back rising into a 

 ridge j colour yellow, barred from head to tail with deep chest- 

 nut fasciae, widening on the abdomen ; body alternately natter on 

 one side than the other. 2 feet long. Sharv, iii. pi. 125. 



Gen. 18. PELAMIS, Cuv. 



Belly and head with larger plates ; occiput tumid on account 

 of the length of the pedicles of the inferior jaw, which is 

 very dilatable ; all the scales of the body small and equal ; 

 tail compressed vertically 



P. bicolor, (Angms platurus, Lin.) Head and upper parts deep 

 black ; lower parts pale yellow ; tail spotted ; back carinated ; 

 scales of the sides small, and brighter yellow. 2^ feet long. In- 

 habits Sea at Otaheite Shaw, iii. pi. 126. 



This species, although poisonous, is eaten at Otaheite. 



Gen. 19. CHERSYDRUS, Cuv. 



Head and body equally covered by small scales ; posterior part 

 of the body and tail compressed vertically. 



C.JasciatuSj Cuv. (Acrochordus fasciatus, Shaw.) Body dusky 

 brown, with carinated abdomen, and whitish ascending lateral 

 bands. 18 inches long. Rivers of Java. Shaw, iii. pi. 130. 



5. With isolated poison fangs. 



The poisonous serpents with isolated fangs have a particular structure in their 

 organs of manducation. The superior maxillary bones are very small, supported 

 on a long pedicle, and very moveable. Into these is fixed a sharp pervious tooth, 

 through which issues, when pressure is applied, a fluid secreted by a gland situat- 

 ed under the eye. It is this fluid which, injected into the wound by the tooth, pro- 

 duces effects more or less serious, according to the species which inflicts the wound. 

 The tooth is concealed in a fold of the gum when the animal does not use it ; and 

 behind are many germs of new fangs, destined to replace the original one, should it 

 be broken by any accident or left in a wound. Naturalists have named these teeth 

 moveable fangs ; but it is properly the maxillary bone which moves. In these serpents 

 there are only two rows of palatine teeth in the upper part of the mouth. All poi- 

 sonous species of which the history is known are viviparous, which has occasioned 

 them to have received the name of vipers, an abbreviation of the term viviparous. 

 The poisonous serpents present exterior characters nearly the same as the preceding 

 genera. But the greater number have the jaws very dilatable, and the tongue ex- 

 tensible. Their head, being broad behind, gives them a ferocious aspect, which 

 in some measure announces their nature. They may be divided into two groups, 

 the Rattlesnakes and Vipers. 



Gen. 20. CROTALUS, Lin. 

 Head broad, triangular, and flattened ; scales carinated ; tongue 



