140 "Journal of Comparative Neurology and Psychology. 



kuckee.* The stomachs of all that I have examined (over twenty 

 specimens) contained the bodies and opercula of these molluscs. 

 When kept in aquaria the opercula are very numerous in the 

 excreta. Adult specimens feed on adult molluscs and young 

 specimens on young molluscs. 



Two methods of feeding prevail. The favorite method seems 

 to be to capture the mollusc when the foot and gills are well out 

 of the shell, to bite off the soft parts and leave the hard shell. 

 To do this the final closure of the jaws must be quite sudden. 

 If they fail to secure the body of the snail in this way they adopt 

 the crushing method. The hard shell is easily crushed between 

 the broad flat jaws and the broken pieces of shell are picked out 

 with the aid of the claws. When in search of food they prowl 

 about the bottom, often underneath the dense vegetation. The 

 heavy growth of Chara or Nitella is tunneled in every direction 

 with passageways made by foraging Graptemys. 



It is impossible to induce them to partake of any food other than 

 that mentioned above. Specimens kept nme months in an 

 aquarium never fed, while other species w^ere eager for any kind 

 of animal food. 



Breeding Habits. — Graptemys begins to lay very early in June, 

 somewhat earlier than other species observed. The females are 

 apt to wander some distance from the water for nesting, seeming 

 to prefer soft plowed soil or clear dry sand away from the beaches. 

 They wander about for hours in search of a suitable place for 

 nesting. One specimen started five nests before she was satisfied 

 with the condition of the soil. Two were rejected on account of 

 the presence of stones and one because the sand caved in too 

 readily. The other two appeared to me to be suitable in every 

 way and I was unable to explain why she abandoned them. 



If one expects to see the first stages of nest-making it behooves 

 him to be astir before sunrise. Over half of the females found 

 nesting were encountered before eight o'clock. They work slowly 

 and seem to prefer the quiet hours of the day, probably because 

 they are less likely to be disturbed. 



Apart from the slowness and deliberateness of their movements, 

 they work much after the fashion adopted by Aspidonectes, 

 except that they never work the fore-feet so as to secure a foothold. 



*This species has been identified for me as Paludina vivipara. 



