WHITEAVE8.J DEVONIAN FOSSILS OF MANITOBA, ETC. 323 



and six or seven on the last, but in larger though less perfect individuals 

 there are nearly if not quite twice this number on the corresponding 

 volutions. 



Pentamerus Point, Lake Manitoba, J, B. Tyrrell and J. F. Whiteave.s, 

 1888 : a single nearly perfect but not very well preserved testiferous 

 specimen. A few sharply defined moulds of the exterior of shells of this 

 species were collected by Messrs. Tyrrell and Dowling, in 1889, at Daw- 

 son Bay, Lake Winnepegosis, on a small island near Beardy Island, 

 at the mouth of 8teep Rock River, about two miles west of Salt Point, 

 and at the mouth of the Red Deer River. 



AsTRALiTES. (Gen. Nov.) 



Shell conical, imperforate, flattened at the base, periphery sub-angular, 

 in the only species known fringed with a thin, regularly lobate or sinuate 

 lateral expansion . columella or internal axis encircled with a single, nar- 

 row but prominent spiral fold, which is represented by a deep spiral 

 groove in casts of the interior. 



The shells for which this new generic name is proposed are essentially 

 similar in their external characters to some I'ecent species of the subgenus 

 Uvanilla, of the genus AstraHum, especially to the U. unguis of Mawe, 

 from south-west Mexico. They bear, also, a considerable resemblance to 

 the Onnfitus (Haliphcebus) alatus of Koken,* from the Devonian rocks of 

 Germany, and to the " alate " PleurotomariiK. They differ, however, from 

 U'vanilla, Onitstus, Pleurotomaria and any other genus that the writer is 

 acquainted with, in the presence of a con.spicuous fold upon the columella. 



The peripheral alation of the outer volution of the typical species of 

 this genus is indicated or preserved in only two of the specimens collected. 

 One of these is an unusually perfect and weH preserved mould of the 

 exterior of nearly the whole of the upper surface of the shell. Figure 10 

 on Plate xlii was drawn from a gutta percha impression of this mould, 

 but a still better impression from it, which shows nearly the whole of the 

 upper side of the peripheral alation, and which is represented on Plate xlv, 

 fig. 6, has since been obtained in wax. The other is the testiferous specimen 

 figured on Plate xlii, fig. 10a, in which the upper or apical portion is 

 buried in the matrix and only the base exposed. From these two speci- 

 mens it is impossible to ascertain whether the peripheral alation is formed 

 of two thin lamellae which coalesce at their sumniit and enclose the slit 

 band, — or solid throughout. If it encloses a slit band, the affinities of the 

 genus are probably with the alate species of I'leurotomaria for which 

 Ferdinand Roemer proposed the genus Uuomphaloj^terus, but if solid, 

 with Astralium or the Onustidoe. 



* Neues .Jahrb. f lir Mineral. , Geol. und Palaeont. , 1889, Beilageband VI, p. 437, 

 pi. xi, figs. 10 and 11. 



