222 MES. JANE LONGSTAFF ON [May 1909, 



matrix, and so much crushed that a just comparison is impossible. 

 It consists of six whorls in a length of 32 millimetres, the greatest 

 breadth being J 2 mm. This example (PI. XI, fig. 3) is from the 

 Lower Ludlow of Dudley. 



At present, this may be regarded as a variety of L. perneri. 

 The discovery of more specimens may prove it to be a distinct 

 species ; while, on the other hand, they may form links connnecting 

 it with the type. 



The example in the Piper Collection is regarded as the holotype. 



LoXONEMA GEAYIANUll, sp. nOV. (PI. XI, fig. 5.) 



Diagnosis. — Shell small, very slender, composed of more than 

 nine whorls. "Whorls flattened or slightly concave above, convex 

 below. Sutures deep, very oblique. Lines of growth fine, curving 

 slightly backward above and more strongly forward below. 

 Aperture unknown. Base convex. 



Remarks and resemblances. — This species is remarkable 

 for its small size and slenderness. In these respects it bears a 

 great resemblance to species of Aclisina, but is devoid of the 

 characteristic spiral ornamentation of that genus. It is distin- 

 guished from L. reedi in the whorls being less concave above and 

 the lines of growth not curving so obliquely backwards. It is most 

 like the drawing of L. dalecarlicum, Lindstr., 1 given by Prof. Koken 

 in ' Die Gastrop. des Baltischen Untersilurs ' Bull. Acad. Imper. 

 Sci. St. Petersb. ser. 5, vol. vii (1897) no. 2, p. 202, fig. 40, 

 but the whorls are more flattened above, and the lines of growth 

 advance more obliquely forward below. It differs from Holopella 

 tenuicincta, M'Coy, 2 in having the whorls flattened above instead of 

 evenly convex, and in having the ornamentation different from 

 M'Coy's figure ; I have not, however, been able to discern the lines 

 represented by him on his type. 



Dimensions. — The holotype, the only specimen known to me, 

 is at Edinburgh, in Mrs. Gray's collection. It is an external 

 mould : therefore the figure is drawn from a wax-impression, which 

 measures 19-5 millimetres in length and 5 - 75 mm. in width. 



Locality and horizon. — Mullock Hill (Ayrshire), in rocks 

 of Lower Llandovery age (Lapworth). 



Loxonema eeedi, sp. nov. (PL XI, figs. 4 a & 4 b.) 



? Loxonema striatissimiim (Salter MS.), Huxley & Etheridge, 1865, Catal. Coll. 



Foss. Mus. Pract. Geol. p. 12. 

 ? MurcMsonia striatissima (Salter MS.), 1878, Catal. Cambr. & Sil. Foss. Mus. 



Pract. Geol. p. 55. 

 Non Loxonema striatissimiim, F. E. Cowper Eeed, 1897, ' The Fauna of the 



Keisley Limestone ' pt. ii, Quart. Journ. Geol. Soc. vol. liii, p. 78 & pi. vi, 



fig. 6. 



Diagnosis. — Shell small, conical, composed of about fourteen 

 whorls. Whorls increasing gradually, smooth, adpressed at the 



1 ' Fragmenta Silurica ' 1880, p. 14 & pi. xv, fig. 19. 'This figure shows no 

 lines of growth.) 



2 ' Brit. Pal. Foss.' 1855, p. S04 k pi. i L, fig. 17. 



