200 CARBOXIFEROrS CEPHALOPODA OF IRELAND. 



occurrence in tlie Coal Pleasures, and present in all the specimens of G. TAs^fi^n 

 I have met with from that horizon. 



It is interesting to learn that ^Ir. James Perrin Smith, who has already done 

 much good work in the embryology of the ammonoids, has made known the 

 occurrence for the first time in America of Gaafriocpras Lhferi, associated with the 

 nearly related species G. carhnnnrium and other Goniatites {(jliipliiiircnif! [Spheiio- 

 reras^ crenistrin, G. [.s'.] .'ifrinfum, G. \^Bej/rirhocpras^ cdhjie)} 



Lornlifi/. — Firoda, a townland and also a hamlet, two and a half miles north- 

 west of Castlecomer, county of Kilkenny. (The specimen prol)alily came from 

 Firoda colliery, in the Kilkenny coal-field, Init as the only locality given is "Firoda" 

 it is not possible to allocate the specimen with precision.) 



Gastrioceras circumplicatile, sp. nov. Plate XLIX, figs. 12 n, J>, \o. 



Description. — Shell small, somewhat inflated, widely umbilicated ; gi-eatest thick- 

 ness at the umbilical margin, about one-half of the diameter of the sheU ; height 

 of outer whorl a little less than one-third of the diameter of the shell. The number 

 of whorls prolialily five or six ; inclusion so nearly complete that only the edges of 

 the inner whorls are exposed. L'mbilicus rather less than one-half of the diameter 

 of the shell in width, deep, with subangular margin. ^Miorl semilunate in section, 

 the height about three-fifths of the breadth ; indented to about one-half of its 

 height by the preceding whorl. Periphery broadly convex, the central part 

 elevated into an obscure ridge ; the narrow lateral area somewhat flattened, merg- 

 ing in the periphery. The ornamentation is very elaborate, and therefore difficult 

 to give an adequate conception of by means of a description. It consists of a series 

 of acute transverse ribs bordering the iimbilicus and radiating therefrom, with a 

 decided inclination towards the aperture. These ribs, which only extend to the 

 width of the lateral area, give rise to a series of fine, raised, crenulated lines ; the 

 latter generall}- bifurcate twice in taking their course from the ribs across the 

 periphery. The space between each set of bifurcating lines is filled up with from 

 thi'ee to four simple lines, which do not, like the ribs, spring from the edge of the 

 innbilicus, but from a point nearly on a level with the bifurcating lines just 

 described. Thus there is a space left between the ribs devoid of any transverse 

 lines ; but this space is not quite smooth, for it is occupied by the fine spiral lines, 

 here much stronger, that cover the whole test. The direction taken by the trans- 

 verse lines upon the surface of the test is as follows : — Starting from the ribs, they 

 curve first forwards and then more sharply backwards, forming a deep and some- 



' "The Carboniferous Ammonoids of America," 'U.S. Geol. Surv.,' Mou. xlii, b»03. pp. 1 — 211, 

 29 plates. (Author's abstract in ' Geologisches Centralblatt," B<1. iii. No. 13, p. 080.) 



