674 DR. GWYN JEFFREYS ON THE MOLLUSCA OF THE [NoV. 14, 



' 2. Propiltdium scabrosum \ Jeffreys. (Plate L. fig. 6.) 



Shell roundish-oval, expanded, rather thin, semitransparent 

 and of a dull hue : sculpture, numerous but not close-set, slight 

 striae which radiate from the beak and are more or less covered with 

 short tubercles, especially behind ; there are also several concentric 

 ridges as in the last-named species: colour whitish: beaJc small, 

 pinched up, incurved, and forming a minute spire of two whorls : 

 mouth roundish-oval: margin thin: inside glossy: septum thick 

 and strong. L. 015, B. 0-15. 



'Porcupine' Exp. 1870: Med. St. Adventure Bank. A single 

 specimen. 



Differs from P. ancyldides in being round instead of oval, and in 

 having much fewer and tuberculated striae ; but I am not quite 

 satisfied that it is more than a curious variety. It somewhat 

 resembles the young of Gadinia garnoti ; but that shell has not the 

 internal septum which is characteristic of the present genus. 



■^ 3. Propilidium pertenue", Jeffreys. (Plate L. fig. 7.) 



Shell oval, convex, very thin and delicate, transparent, and glossy : 

 sculpture, none : colour whitish : beak small, cylindrical, and in- 

 curved, forming a minute spire of two whorls : mouth oval : margin 

 even ; inside glossy : septum small. L. 0"1, B. 0'075. 



'Porcupine' Exp. 1870: Atl. St. 17, 17 « (4 specimens); Med. 

 off Rinaldo's Chair (1 specimen). 



Distribution. Palermo (Monterosato) ; 162g fras. 



The young of P. ancyldides, much smaller than the species now 

 described, are more expanded or depressed, and have the same 

 sculpture as the adult ; they are also proportionally solid as well as 

 of a dull hue. 



The inner layers of most of the specimens are permeated by a 

 microscopic and branching spore-like organism, perhaps of a fungoid 

 nature. 



An imperfect specimen of another small and apparently distinct 

 species occurred also in Station 17. It has the characteristic septum, 

 but otherwise resembles a Lepetella. Tiie beak is very much shorter 

 than in P. pertenue ; and the spire has barely one turn. 



I had originally given the species above described the MS. name 

 tenue. 



i/ 4. Propilidium compressum^, Jeffreys. (Plate L. fig. 8.) 



Shell differs from P. pertenue in being oblong instead of oval, 

 and in being laterally compressed like Patella \_Lepetella'] latero- 

 compressa of Rayneval, a Monte-Mario fossil and, according to 

 Dr. Tiberi, living in the Bay of Naples ; and it is also not quite 

 smooth, but is marked by a few slight longitudinal striae ; the beak 

 is proportionally longer, somewhat twisted to one side, and nearly 

 overhangs the hinder margin, instead of being placed (as in P. per- 

 tenue) at about one third of the distance from it. L. 0-1, B. 0"06.5 



'Porcupine' Exp, 1870: Atl. St. 17. A single specimen. 



' Roughened. * Very thin or slight. ^ Pressed togetlier. 



