56 DEVONIAN PAUNA. 



differing in having the ornament continued all over the whorls, and in having a 

 very definite sinus-band, bounded by threads. The longer variety figured by 

 Sandberger is a totally different shell from ours. 



VI. Family — PLEUROTOMAuiiDiE, cVOrhigny, 1842. 

 1. Genus — Pleueotomaria, Defrance, 1826. 



1. Pleurotomaria gracilis, Phillips. 



1892. PLEuiiOTOMAEiA GRACILIS, Whidbome. Dev. Fauna, vol. i, p. 303, pi. 



xxviii, fig. 18. 



Bemarhs. — I have found no specimens referable to this species in the Pilton 

 Beds, but Phillips quotes it from Brushford aud Baggy Point. His figure shows a 

 distinct sinus-band, and if that is correct it is certainly distinct from Bhaphistoma 

 Junius, which approaches it in general shape. 



2. Pleurotomaria Hamlingii, n. sp. Plate VI, figs. 9, 9 a. 



1841. Pleuuotomaeia aspera, Phillips (pars) (not Sowerhy). Pal. Poss., p. 96, 



pi. xxxvii, figs. 177 a, b (only). 

 1889. — DiSTiNGUENDA, Whidbome. Geol. Mag., dec. 3, vol. vi, 



p. 30. 

 1892. — __ _ Dev. Fauna, vol. i, p. 290. 



Description. — Shell small, trochiform, turrited, of equal height and width. 

 Spire elevated, rather slowly increasing, consisting of at least four whorls. 

 Suture obtuse. Whorls narrow, sloping out from the suture in a concave curve 

 to the shoulder, where they suddenly turn thi'ough a blunt angle, and then 

 proceed perpendicularly downwards for about the same distance to the lower 

 suture. Sinus-band situate on the shoulder, and consisting;- of an excavate groove, 

 which is bounded above and below by a thread-like ridge, and has a row of 

 small beads or nodules along its centre. Ornament consisting of (1) a row of 

 small nodules, halfway between the suture and the sinus-band, and a second row 

 of still smaller nodules halfway between this first row aud the sinus-band ; (2) two 

 equidistant rows of small nodules, the upper row of which is the smallest, situate 

 upon the lower or perpendicular part of the whorl ; and (3) minute, transverse 

 elevated threads, which arch gently backwards on the upper part of the whorl, and. 



