CHAPTER VI. 



Division III. Proteroglypha. 



{The Front-fanged Snakes.) 



Sub-family IV. Hydrophin^. 



The Sea Serpents belong to the division of snakes known as the 

 Proteroglypha, so called because they have fangs in the front 

 part of the upper jaw. These fangs, which are set in the anterior 

 maxillary bone, are deeply channelled or grooved, the sides of 

 the channels showing a tendency to unite and form a complete 

 perforated or hollow tooth similar to the hollow fangs of the 

 Viper family. These are the typical poison fangs. Independent 



Fig. 65. — Head and neck of the poisonous Black and Yellow Sea 

 Snake of the African Coast (Hydrus platurus).* 



of the fangs there is a set of small soHd teeth, also set in the front 

 part of the upper jaw. 



The sub-family Hydrophins are all Sea Snakes. There are 

 about fifty- five species or kinds known. 



* Sea Snakes have small scales on theunderparts of their bodies. Land 

 Snakes, on the contrary, have broad shields running right across from side 

 to side. 



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