144 PROCEEDINGS OF THE ACADEMY OF [Mar., 



Hither, as in other parts of the swamp, the bears, raccoons, opos- 

 sums and other mammals come for the eggs buried in the sand. 

 Over this same ground the king snake, black snake and pilot snake 

 search for the same quarry and the reptiles which lay the eggs. 

 The natives have a very good idea of the economic value of the 

 various snakes and spare most of them, except the truly poisonous 

 forms and what they call the "Water" and "Highland Moccasins" 

 {Tropidonotus and Thamnophis). One of the many roles which the 

 natives accredit the black and turkey vultures is that of enemies of 

 snakes and some birds of prey, e.g., the Buteos engage in the same 

 practice. The snakes also suffer from the herons, ibises and cranes, 

 but with these the reptiles are a second choice when frogs and toads 

 are available. 



The number of snakes with internal parasites is surprisingly 

 large, 37 of the 165 being thus afflicted, or 8 of the 21 species. They 

 are: 



Heterodon platyrhinus 14 Thamnophis s. sackeni 2 



Ancistrodon piscivorus 6 Lampropeltis getuliis 1 



Coluber constrictor 5 Sistrurus miliarius 1 



Tropidonotus taxispilotus 5 



Thamnophis s. ordinatus 3 37 



No doubt, other species also suffer, for this list represents the 

 species of which we had the largest series. The above species are 

 about equally distributed between the terrestrial and aquatic groups. 

 In number, the former are 24 and the latter 13; but, if the spreading 

 adder be eliminated, the terrestrial forms lead by 3. It is a significant 

 fact that the species which are the worst sufferers are also inveterate 

 feeders on toads and frogs of all kinds, and it is quite possible that 

 these nematodes and other parasites reach the snakes through their 

 food. 



According to habitat, these snakes may be divided as follows: 



Islands. 



Heterodon platyrhinus, Elaphe ohsoletus. 



Coluber constrictor, Opheodrys cestivus, 



Lamprojjeltis getulus, Diadophis punctatus, 



Crotalus adamanteus, Elaphe guttatus, 



Crotalus horridus, Storeria dekayi, 



Sistrurus miliarius, Storeria occipitomaculata, 



Thamnophis s. ordinatus, Haldea striatula, 

 Lampropeltis d. coccineus, 



