1877. J MR. E. A. SMITH ON SHELLS FROM LAKE NYASSA. 713 



are fine, and about eighteen on a whorl, those on the penultimate 

 volution bearing about eight nodules. 



2. Melania turritispira. (Plate LXXV. figs. 14, 15.) 



Shell small, turreted, ovately fusiform, pale olive ; whorls seven 

 or eight, flat, with a raised infrasutural belt, furnished with coarse 

 ribs, and sculptured with a few spiral striae, nearly obsolete on the 

 upper whorls, except the one which marks off the raised band at the 

 suture ; on the body-whorl the ribs become obsolete at the middle, 

 where it is angulated, and the transverse striae are about eight in 

 number ; the three or four upper ones crossing the costae give them 

 a somewhat nodose appearance ; aperture small, subovate, acuminate 

 above. 



Length 8 millims., diam. 3 1. Aperture 3 long. 



This curiously short stunted-looking species is remarkable for its 

 peculiar form, the turreted spire, and the strongly developed nodu- 

 lous upper extremities of the longitudinal ribs forming an infra- 

 sutural belt. 



Certain varieties of Iff, polymorpha approach the present species 

 in the style of sculpture ; but the very different form of the latter 

 and the absence of spotting easily distinguish it. 



The specimens now described may not be full-grown ; but it is to 

 be presumed that larger examples would still exhibit the same short 

 stunted form. 



3. Melania pupiformis. (Plate LXXV. fig. 13.) 



Shell cylindrical, subpupiform, covered by a greyish epidermis ; 

 whorls nine, flattish, constricted just beneath a raised belt at the su- 

 ture, somewhat turreted, separated by a deep suture, furnished with 

 coarse flexuous ribs, which are nodulous at the upper extremities 

 through being crossed or intersected by a spiral furrow a little 

 beneath the suture ; below this there are faint indications of one or 

 two other transverse striae, giving the ribs a subnodose appearance. 

 On the body-volution the ribs are almost obsolete ; but around the 

 middle two or three spiral sulci are more distinct than those on the 

 upper portion of it- Aperture small, acutely ovate, occupying lesa 

 than one third of the whole length of the shell. 



Length 1 1 miUims., diam. 3J. Aperture 3|^ long. 



The cylindrical pupoid form of this little species is very remark- 

 able. The last three whorls are of about the same diameter ; and 

 above these the spire rapidly diminishes, forming a short cone at the 

 apex. The ribbing is very strong for so small a shell. 



Only two examples of this species have come under my observa- 

 tion ; but Mr. Simons informs me that he has seen several others, 

 and among them some which were larger than that now described, 



4. Melania simonsi. (Plate LXXV. fig. 3.) 



Shell acutely pyramidal, thinnish, whitish spotted with red ; 

 whorls 9-10, divided by a deep, slightly oblique suture, but little 

 convex, furnished with obliquely arcuate granulous ribs, which uum- 



