STROBILOPS, S. G. ENTEROPLAX. 53 



carinate at the periphery, obtusely angular around the um- 

 bilicus. Aperture diagonal, lunar, the peristome thickened 

 within, expanded and slightly reflected, margins joined by a 

 callus. Two parietal lamellae, one reaching the edge of the 

 parietal callus, the other stopping a little short of it; both 

 penetrating deeply inward; at a third of a whorl within are 

 5 or 6 thin, rather long lamellae on the palatal margin oppo- 

 site (Mlldff.). 



Height 2%, diam. 4 mm. (Mlldff.). 



Cebu: peak of Mt. Licos (Moellendorff). 



Plectopylis trochospira Moellendorff, Jahrb. D. Malak. 

 Ges. XIV, 1887, p. 273, pi. 8, figs. 9-9c ; Abh. d. naturf . Ges. 

 Gorlitz, 1897, p. 148.— Gude, Science Gossip, IV, March, 1898, 

 p. 285, fig. 73. 



I have not seen this species, of which Gude writes : 



''The aperture is diagonal, lunate; the peristome white, a 

 little thickened and reflexed, the margins being slightly con- 

 vergent and united by a scarcely raised sinuous ridge at the 

 parietal callus. The parietal armature consists of two long, 

 parallel, horizontal folds, which revolve over nearly half a 

 whorl, the upper one being the stronger and united to the 

 ridge at the aperture, while the lower one is thinner and 

 terminates at a short distance from the ridge; a very thin, 

 short, horizontal fold occurs posteriorly a little below the 

 upper fold (see fig. 6e, which shows the parietal wall of the 

 shell with its folds). 



' ' The palatal armature is composed of five short, thin, hori- 

 zontal folds, which descend a little anteriorly (see fig. 6d, 

 which shows both the parietal and the palatal armature from 

 the posterior side). The specimen figured is in the collection 

 of Professor Oscar Boettger, of Frankfort, by whom this shell 

 — which measures : major diameter, 4 millimeters, minor diam- 

 eter, 3.5 millimeters; altitude, 2 millimeters — was obligingly 

 lent to me. 



"Plectopylis trochospira is allied to P. quadrasi, but it is 

 larger and much lighter in color; there are also certain dif- 

 ferences in the armature" {Gude). 



