706 AUP PENG DWEXs I. 
might have some relation to an alate Avicula. The surface is distinctly marked with 
broad flat coste, as represented in the figure. The specimen is from Illawarra. 
c. Mollusca Gasteropoda. 
71. Prixopsis TENELLA (Dana).—Short conical, oblong, acuminate at apex, and very 
slightly recurved. Apex anterior to centre, but situated over the base ; aperture ovate- 
elliptical, entire, half narrower anteriorly. Surface smooth. Length of aperture § inch; 
breadth g inch; height of cone same as breadth.—Plate 9, figs. 13 a, 6, different views, 
natural size. 
Harper’s Hill. 
Patella tenella, Exped. Foss., Amer. Jour. Sci., ii. Ser., iv. p. 151. 
72, Prteopsts atta (Dana).—High, compressed, conical; (height fully as great as 
length,) acuminate above, and apex much recurved forward, and projecting beyond the 
base. Base narrow elliptical, its length more than twice the breadth.—Plate 9, fig. 14, a, 
natural size; b, under view of same. 
Harper’s Hill. 5 
The specimen here described belongs to the collections of Rev. Mr. Wilton of New- 
castle. The description has been drawn up from a figure of it, made by his permission. 
73. PLreuroromartA Morristana.—Conical, a little oblong, angle of spire about 35°, 
whorls about 4, convex, carinate, carina subacute, an upper carina obsolescent, a lower 
distinct. Aperture orbiculate-——Length 8 lines ; breadth below, 5 lines.—Plate 9, fig. 
15, specimen from Illawarra, natural size ; 15 a, portion enlarged ; fig. 16, specimen from 
Harper’s Hill, natural size. 
Black Head, District of Illawarra, and also Harper’s Hill. 
The specimens from Harper’s Hill are mostly larger than those from Illawarra, the 
latter seldom exceeding a length of 6 lines. In the enlarged figure, it is observed that 
there are two concave lines encircling the spire; and, as usual, the direction of the lines 
in each, show the direction of the lines of growth. 
I have adopted M’Coy’s specific name, in preference to my own of earlier date, as the 
honour is well due to Mr. Morris, the author of the chapter on Fossil Australian Mol- 
lusca in Strzelecki’s valuable work, 
Pleurotomaria trifilata, Exped. Foss., Amer. Jour. Sci., ii. Ser., iv. 151. 
Pleurotomaria Morrisiana, M’Coy, loc. cit. vol. xx. 306, pl. 17, fig. 5. M’Coy observes that 
the species occurs in the sandstone of Muree, N. 8. W., as well as of Wollongong. 
74, PLevroTromaria NupA (Dana).—Short conical, angle of spire about 115°, whorls 
4 or 5, rounded, separated by a suture, smooth, slightly carinated, with another obsolete 
carina either side.—Length half an inch; breadth about 7 inch.—Plate 9, fig. 17 a, b, ¢, 
different views, natural size. 
Harper’s Hill. 
Pleurotomaria nuda, Exped. Foss., Amer. Jour. Sci., ii. Ser., iv. 151. 
