312 



MR. S. C. SARKAR on the BUCCAL GLANDS 



The diTct of the poison gland, like that of Tropidonotus, 

 opens into the vestibule which communicates with the tooth sac 

 at one end, and at the lower end opens into the buccal cavity 

 {op. cl.p.g.). A comparison of the course of this duct in 

 Tropidonotus and Lycodon reveals the fact that in Lycodon the 

 communication of the vestibule with the tooth sac is higher than 

 in Tropidonotus, so that the secretion of the gland first fills the 



Text-figure 15, 



op.dp.g. 



Lycodon aulicus. Transverse section of head in the region of the fang, dnct of the 

 poison gland and its opening into the tooth sac and the buccal cavity, ves. 

 vestibule ; other letters as before. X 63. 



cavity of the tooth sac while on its course downwards into the 

 buccal cavity. By such an arrangement of the duct the tooth- 

 cavity is kept filled with the poison, and the tooth bathed in it. 

 In this way a greater amount of poisonous fluid can be injected 

 into the bigger wound, which is made by the two cutting-edges of 

 the lancet-shaped tooth. 



OxYBELIS FULGIDA. 



Opisthogylpha. 



This is a very interesting snake because of the fact that 

 although it has acquired a better and surer means of injecting 

 poison into the wound by developing a groove in the fang, it still 

 retains the ancestral method of filling the tooth sac with the poison. 

 West has described the anatomj'^ of the head in detail, but for 

 the present purpose of comparison his figures are insufiicient. 

 I have been unable to procure any specimens of Oxyhelis to verify 

 West's observation, and therefore cannot provide the necessary 



