Vol.62.] OMOSPIBA, LOPHOSPIBA, AND TURBITOMA. 



565 



Pig. 3. — Lopho- 

 spira bellicari- 

 nata, sp. nov., 

 penultimate wliorl 

 magnified 3 dia- 

 meters. From the 

 Middle Bala of 

 ShallocJc Mill. 



Lophospiba bellicakinata, sp. nov. (PL XLIY, fig. 5 & text-fig. 3.) 



Diagnosis. — Shell turreted, composed of more than six whorls. 

 Whorls strongly angular above the middle of the body- whorl, and 

 slightly below the middle of the earlier whorls; surface deeply 

 excavated above the angle and more or less concave below. Sinual 

 band situated on the angle, having a very prominent central keel 

 and a slighter one bordering a groove on each side. Ornamentation 

 consisting of a keel a short distance below the upper suture, and 

 another below the band which appears just above the lower suture 

 on the anterior whorls of the spire. Lines of growth strong and 

 distinct, curving back to the band above and 

 coming down almost vertically below, forming 

 crescents on the band which indicate a sinus 

 of moderate depth. Base convex. Aperture 

 imperfectly known, produced ; no indication 

 of an open umbilicus. Test thin. 



Remarks and Resemblances. — Mrs. 

 Gray's collection contains two specimens of 

 this species : that figured in PL XLIY, fig. 5 

 is fairly well-preserved, the other is very im- 

 perfect. Among British shells it most nearly 

 resembles Pieurotomaria turrita, Portl., 1 but 

 is distinguished by the central keel of the band 

 being more prominent, the upper and lower 

 keels being stronger, the whorls more excavated 

 above, and the lines of growth being less 

 oblique. The American species which it is 

 most like is L. Saffordi, Ulrich, 2 from which it differs in being 

 rather slighter, the band somewhat wider, its central keel sharper 

 and more prominent, and the lines of growth less oblique. 



Dimensions. — Length of specimen figured, consisting of five 

 whorls, = 30 millimetres ; width of penultimate whorl = 16 mm. 

 The other example is smaller, and consists of about six whorls in a 

 length of 17 mm. 



Locality and Horizon. — Shallock Mill (Ayrshire), in rocks 

 of Middle Bala age [Lap worth]. 



Tubulosa Subsection. 

 Lophospira cyclonema (Salt.). (PL XLIY, figs. 6-9.) 



Murchisonia cyclonema, J. W. Salter, 1873, ' Catal. Cambr. & Silur. Foss.' p. 155. 

 Murchisonia corpulenta, W. J. Sollas, 1879, Quart. Journ. Geol. Soc. 

 vol. xxxv, p. 499 & pi. xxiv, fig. 11 ; A. C. Kamsay, 1881, Mem. Geol. Surv. 

 vol. iii, ' Geol. North Wales ' 2nd ed. p. 461 ; R. Etheridge, 1888, ' Foss. Brit. 

 Is. vol. i (Palaeozoic) ' Appendix, p. 418. Murchisonia cyclonema, H. Woods,. 

 1891, 'Catal. Type Foss. Woodward Mus.' p. 107. Pieurotomaria cyclo- 

 nema, F. R. C. Reed, 1901, Geol. Mag. dec. iv, vol. viii, p. 248 & pi. xi, 

 figs. 1-3. 



Diagnosis. — Shell somewhat short, robust, turbinate, composed 



1 ' Rep. Geol. Londonderry, &c. ' 1843, p. 413 & pi. xxx, fig. 7. 



2 Final Rep. Geol. & Nat. Hist, Surv. Minnesota, vol. iii, pt. ii (1897) 

 p. 982 & pi. Ixxiii, figs. 49-51. 



