GLYPIIIOCEHAS (BEYRICHOCERAS) SPHENOIDALE. 17:5 



of Glyphioceras truncatwm, the resemblance to this series in other features is note- 

 worthy, especially in the flattened sides and truncated periphery. The suture-line 

 also is not very dissimilar, comparing together, e. </., the suture-line of G. <lijji<-ilr 

 with that of G. subquadratim (PL XL VI, figs. 1 c and 2 c). 



Remarhs. — The specimen from which the above description was chiefly drawn 

 up having come unexpectedly into my hands after the plates had all been printed, 

 I have not been able to figure it; the one referred to at the head of this description 

 must therefore suffice to represent it, and it in fact gives all essential features, the 

 details of the umbilicus being alone deficient ; these are supplied by the recently 

 available specimen. The latter thus fulfils the double office of amplifying structural 

 details, and of confirming the existence of a specific form whose validity might, 

 upon the evidence of a single specimen, have been called in question. 



Locality. — Little Island, near Cork. 



G-lyphioceeas (Beyrichoceras) sphjeroidale ? M'Coy. Plate XLVi, figs. 3 a, b; 



5 a, l>. 



1844. Goniatites si'ii.EiioiDALis, F. M'Coy. Synops. Carb. Foss. Ireland, p. L5, 



pi. iv, fig. 18. 

 1850. Aganides si>h/eiucus (pars), A. d'Orbigny. Prod, de Paleont. stratigr., 



vol. i, p. 115. 

 1852. Ammonites si'h.ki.k'us (pars), ('. G. Giebel. Fauna der Vorwelt, Bd. iii, 



Abth. i, p. 471. 

 L854. Goniatites sph/eroidalis, J. Morris. Cat. Brit. Fuss., 2nd ed., p. 304. 

 1862. li. Griffith. Journ. Geol. Sue. Dublin, vol. i.\. 



p. 55. 

 L880. L. G. de Koninclc. Faune Calc. Carb. Belgique 



(Ann. Mus. Roy. d*Hist. Nat. Belgique, 



ser. Paleont., torn, v), pi. 2, p. 99, 



pi. xlvii, figs. 6, 7 ; pi. xlviii, figs. 10 — 12. 



1889. Glyphioceras sraiEEoiDALE, K. Uolzapfel. Palaeont. Abhandl., Dames 



und Eayser, Bd. v, i, p. 30. 

 L897 A. H. Foord cvnd G. 0. Crick. Cat. Poss. 



Ceph. British Museum, pt. :>. p. 183. 



Description. — Shell spheroidal, somewhat compressed laterally, rather widely 

 umbilicated ; greatest thickness at the margin of the umbilicus, about four-sevenths 

 of the diameter of the shell, height of outer whorl about three-sevenths of thai 

 diameter. Number of whorls unknown. Inclusion fully three-fourths. Umbilicus 

 probably of moderate depth, hut not fully available for examination. Whorl scmi- 

 lunate in section, nearly twice as wide as high, indented to about three-fourths of 



