APTYXIELLA. 191 
Famity—NERIN HIDA. 
* Shell turrited, subcylindrical, conical or ovate-elongate, solid, thick; aperture 
slightly channeled in front. . . . Columella or walls of the aperture furnished 
with folds, which are continued into the whorls of the spire.’’—FiscuEr. 
The author of the ‘ Manuel de Conchyliologie’ is evidently disposed to agree 
with Blainville and Woodward in placing the Nerinzide in close relationship to 
the Cerithiide rather than to the Pyramidellide, in accordance with the views of 
Defrance and D’Orbigny. The family is almost entirely composed of one genus, 
Nerinea (including sub-genera, such as Ptygmatis, &c.); but, as if to show that no 
family can be constituted without an exceptional member, there is just one 
limited genus which violates the rule as to the existence of internal folds. 
Genus—ApryxiELLa, Fischer, 1885, ‘ Manual,’ p. 689; = Pacuysrytus, 
Gemmellaro, 1878; == Aptyxis, Zittel, 1873. 
Shell conical-elongate, subcylindrical, not wmbilicated ; whorls numerous, not 
embracing. Aperture quadrangular, terminating anteriorly in an insignificant canal ; 
no internal folds on the columella and walls. 
The above diagnosis is a modification of those given by Gemmellaro and 
Fischer. The former regards Pachystylus as belonging to the Pyramidellide ; 
three species are described by him from the white crystalline Limestone of 
Montagne del Casale. Fischer gives as an example of the genus Aptyriella 
sexcostata, D’Orb., from the Corallian of La Rochelle. 
120. ApryxIELLA suBcONICA, sp. nov. Plate XII, figs. 10, 11. 
Description : 
Probable length 5 ; é . 59 mm. 
Width about , ‘ : . th. 
Spiral angle about . : : 2) 10%. 
Shell elongate, subcylindrical; whorls numerous, concave, the width of one 
whorl being nearly equal to its own height, plus that of the preceding whorl. The 
whorls are apparently smooth, but the available specimens are much worn. 
