554 MISS JANE DONALD ON THE GENEEA [Nov. I906, 



Remarks and Resemblances. — There is one undoubted 

 specimen of this species in Mrs. Gray's collection, and two others 

 which probably belong to it, but they are much crushed and do not 

 show the band or sinus distinctly ; the lines of growth, however, 

 indicate that the band was immediately above the angle. One is 

 entirely an internal mould ; the other shows some portions of the 

 external mould, as well as the internal. Both the internal moulds 

 have an open umbilicus ; but it is impossible to tell from them 

 whether it was so originally, as the test may have filled up the 

 cavity. The best example is somewhat crushed downwards ; it 

 has the base of the sinus intact, but, as the whole of the outer lip is 

 not seen, it is probable that the sinus may have been deeper than 

 appears in the figure. Portions of the rock covering the shell have 

 been retained, and by pressing wax into these the form of the sinus, 

 and also of the band on a higher whorl, are better seen than on the 

 specimen itself, which is more or less an internal mould. 



This species has somewhat the appearance of a Lopliospira, but 

 an examination of the band shows it to be quite distinct from any 

 members of that genus. It differs from the two species, 0. lati- 

 cincta, Ulrich, 1 and 0. Alexandra, Billings, referred by Dr. Ulrich to 

 the genus, in the whorl being longer above the angle : this appear- 

 ance of length is, at any rate, partly increased by the shell being 

 compressed downwards, and it is not so marked on the fifth whorl, 

 which does not seem to have suffered so much by pressure. The 

 band also is not quite so wide in proportion. It comes nearest 

 to 0. laticincta, where the periphery is more angular than in 

 0. Alexandra and the spiral angle is greater. 



Dimensions. — Length of the specimen figured, PI. XLIII, fig. 1, 

 = 24 millimetres; width = 20 mm. Depth of the sinus = about 

 6*5 mm. 



Locality and Horizon. — Thraive Glen (Ayrshire) in the 

 .Starfish Bed, a coarse-grained rock of Upper Bala age [Lapworth]. 



Lophospiea, Whitfield. 



I gave a brief description of the genus Lophospira, Whitfield, 

 in my paper of 1902, and also there described three species. 

 I now propose to discuss it more fully, giving diagnoses of the other 

 British species with which I am acquainted. The genus was 

 created by R. P. Whitfield in 1886, 2 when he gave Murehisonia 

 bicincta, Hall, as the type, and his description was afterwards 

 emended by Dr. Ulrich. 3 I here append a diagnosis of the genus, 

 which appears to sum up the chief characteristics. 



Diagnosis. — Shell more or less elongated, consisting of numerous 

 whorls. Whorls angular, closely coiled throughout, or only in the 

 earlier stages, the later whorls often becoming disconnected. The 



1 Final Eep. Geol. & Nat. Hist. Surv. Minnesota, toI. iii, pt. ii (1897) 

 pp. 945-46 & pi. lxx, figs. 64-67. 



2 Bull. Amer. Mus. Nat. Hist. vol. i, p. 312. 



3 Op. supra cit. pp. 951 & 960. 



