50 SUTER : COMMUNICATIONS FROM NEW ZEALAND. 



side. In P. nrtiula only about the first two whorls are calcareous, 

 the remainder consisting simply of conchin. I found this out in the 

 following way. Having received a specimen of that mollusc preserved, 

 unfortunately, in strong alcohol, I was unable to remove the hardened 

 animal without destroying the shell, and the idea struck me (also un- 

 fortunate!) of removing the animal by immersing the whole specimen 

 in a solution of caustic potash. The result was a dark brown solution; 

 the first two calcareous whorls intact, the radula, and a fine, brown 

 membrane from the periostracum swimming in the liquid ! 



The situation of the eyes in Paryphafita and Rhytida differs some- 

 what from that in the Helicidae. In the latter the eyes are not quite 

 at the top of the ommatophores, but on their upper side; in our two 

 genera of carnivorous snails however they are still much more removed 

 backward, as fig. \a shows. This is most likely due to a great devel- 

 opment of the olfactory bulb, as these molluscs have to hunt for their 

 food under moss, in loose mould, etc., where eyes cannot be of much 

 use. I give here a figure of R. greetiwoodi (PI. iii, fig. i) drawn from 

 life, which shows the presence of small buccal papillae. 



77/1? food of Paryphania 07id Rhytida consists no doubt chiefly of 

 earthworms, at least in captivity they readily feed on them. They 

 extend the odontophore, hook the worm with the long sharp teeth on 

 the former, and by withdrawing the tongue the worm passes slowly 

 down into the stomach. During that operation all the tentacles are 

 retracted, no trace of them can be seen. Occasionally they also feed 

 on other molluscs, and it is significant that in the same situations 

 where Paryphanta shelters during the winter months Athoracophorus 

 is also found. To a specimen of R. greenwoodi I gave two living 

 Flatumtdina thaisa ; the following day I found the latter shells quite 

 empty, not a trace of the animals left, one specimen with one large, 

 the other with two smaller holes rasped out at the base, through 

 which the tongue of Rhytida could be passed to extract those parts of 

 the animal lying behind the columellar muscle. They do not touch 

 introduced slugs, such as Limax agrestis, the sticky slime is probably 

 not to their liking. 



It IS not difficult to keep Paryphanta and Rhytida in captivity for 

 a considerable time if they are provided with sufficient moisture, a 

 good quantity of fresh moss and earthworms for food, but I have 

 never observed them copulate or even lay eggs. 



The radula. — It is not always easy to say whether any given 

 species has a rhachidian tooth on its radula or not. This tooth is cer- 

 tainly the first worn or broken off", and I have seen many odontophores 

 on which for the whole length only a few central teeth could be made 



