S16 MB. G. S. WEST ON" THE BTJCCAI, GIATTDS AlfD [NoV. 19, 



The arteries supplying the Harderian and poison-glands arise 

 from the ophthalmic artery which crosses the lower half of the 

 orbit. The branch to the Harderian gland arises from one side, 

 and that to the poison-gland on the other, just before this artery 

 enters the orbit. The branch to the poison-gland enters that 

 about the middle and then bifurcates, one branchlet running 

 anteriorly and one posteriorly. Side by side with these arteries 

 there run corresponding veins. The labial glands are supplied by 

 branches of the maxillary and mandibular arteries. 



These statements are based upon observations made upon the 

 undermentioned genera, each of which may now be dealt with in 

 greater detail. 



Genus Dipsas. 



Species examined : — D. irregularis, D. ceylonensis, D. fusca, and 

 D, dendrojphila. 



The poison-gland in all the species is clearly definable from the 

 superior labial gland ; the latter extends anteriorly but a short 

 distance in D.fusca(V\. XLIY. fig. 1) and D. ceylone.isis, whereas in 

 B. dendrophila and more especially in D. irregularis it extends to 

 the anterior extremity of the ]a\v. The inferior labial gland is also 

 more extensive in the latter species. The lobules are much 

 smaller in D. fusca and D. irregtdai-is than in D, ceijlonensis and 

 D. dciulrojihila. The Harderian gland is two-lobed in B. fusca and 

 D. ceylonensis (PL XLIV. figs. 6 and 7), but three-lobed in the 

 other two species, two of the lobes being within the orbit 

 (PL XLIV. fig. 5). The maxilla of D. fusca (PL XLIV. fig. 2) 

 possesses much fewer teeth than those of the other three species. 

 There are 7 solid teeth and 3 posterior grooved teeth ; of the 

 latter, two are large ones and the third is much smaller and more 

 curved. D. dendroj)hila and D. irregularis each possess 3 posterior 

 grooved maxillary teeth, the terminal one in each case being the 

 smallest (PL XLIV. fig. 4). The maxilla of the former has 

 12 solid teeth and that of the latter 1-i. The maxilla of D. cey- 

 lonensis (PL XLIV. fig. 3) possesses 2 large grooved teeth of equal 

 size and 12 solid ones. 



Genus Dexophis. 



Species examined : — D. prasinus and D. mycterizans. 



The poison-gland in this genus is proportionately smaller than 

 in any other genus examined, and superficially is not readily dis- 

 tinguished from the ^upei-ior labial gland (vide PL XLIV. fig. 11). 

 The Harderian gland is of very small bulk and consists of a mere 

 strip of glandular tissue under and posterior to the eye (PL XLIV. 

 fig. 14). The maxilla of D. mycterizans (PL XLIV. fig. 13) possesses 

 4 anterior small teeth, three median large ones, then 5 more small 

 ones, and finally two large grooved teeth. That of D. prasimis 

 (PL XLIV. fig. 12) possesses 5 anterior small teeth, a median very- 

 large and stout tooth, then 4 more small ones, and finally one 

 large grooved tooth. The grooves of the posterior maxillary 



