140 GIBBONS : NEW EAST AFRICAN LAND SHELLS. 



Delagoa Bay and Port Natal, distinguished by its larger size, 

 paler color, and coarser granulations on shield. 



The slit in the shield is capable of considerable enlargement; 

 sometimes a good deal of the spire is visible, usually the orifice 

 is so contracted that none of the shell can be seen. I once saw 

 milky mucus exude from the slit. 



A comparison of this mollusc with the animal of any of the 

 S. E. African Nanince shews some interesting points of resem- 

 blance; in both there is a furrow running from head to above 

 mucus pore, below which the surface is smooth and mucus- 

 secreting; the pore is common to both, and the caudal spine of 

 Nanina is indicated in Urocyclits by the peaked termination of 

 the integument behind; lastly, if we suppose the orifice in the 

 shield of Urocyclus to be greatly enlarged, and the rudimentary 

 shell developed, we shall have an arrangement of the shield similar 

 to the collar of iV«;////«-viz.,part investing the peristome of shell and 

 part covering dorsum of body. Hyalimax is probably related to 

 Urocyclus, but judging from description"^ the closest ally is He77ip- 

 /liUia, in fact they appear to agree in external generic characters, 

 except that the latter has the shell more exposed, or, in other 

 words, the slit in the mantle larger. 



Li max, sp. indet. 

 A small brown Lhnax is of somewhat rare occurrence at 

 Zanzibar. 



Onchidium, sp. indet. 

 I found specimens of the above on moss in ravines; Bawri 

 Island, Zanzibar Channel. 



Vaginulus Natalensis, V. Rapp.? var. 



Krauss, Siidafr. Moll., p. 72. 



Body oblongo-elliptical, depressed, keeled longitudinally, sides 

 sloping from keel to margin and hardly convex, ends rounded, 



* Terr. Air-Breathing Molluscs, N. Am., v., p, 246. 



J.C, ii., May, 1S79 



