GONIATITES. 61 



has much finer and less oblique striae, wider sides, a less prominent keel, and an 

 umbilicus with less sloping sides. In G. NoeggeratJii, von Buch/ the median 

 saddles seem much deeper, so that the median lobe is thrown much further back, 

 and the sides of the shell seem shorter and flatter. Lastly, G. intumescens 

 (Beyrich)^ is deeper and more ovoid in section, has a smaller aperture, and is 

 smooth. Sandberger figures^ several extreme varieties of the latter species, none 

 of which are at all like our Devonshire shell, and which show that the sides of 

 the mouth were differently formed, and that the strige had a different course. 



3. GrONIATITES TRANSITORIUS, Phillips. PI. V, figs. 7 — 10 ; PL VI, figs. 8, 8 a. 



1841. GoNiATiTEs TRANsiTORitrs, PJiiU. Pal. Foss., p. 140, pi. Ix, fig. 227*. 

 1851. — BiGiLif&.i,icvLATva, Sandb. Verst. Eliein. Nat<8au,p. 112, pi. si, 



figs. 5, G. 

 P1843. — iEQUABiLis? F. A. Bom. (dou Beyrich). Verst. Harz , p. 34, 



pi. ix, figs. 13 a, h. 

 1888. — TBANsiTOEius, EtJieridi/e. Foss. Brit., vol. i, Pal., p. 168. 



Description. — Shell small, flattish, elHpsoidal, consisting of about four whorls. 

 Umbilicus very open and rather shallow, nearly half the diameter of the shell in 

 width. Whorls increasing rapidly, subtriangular in section, being truncated at the 

 back and rounded at the dorsal corners, only slightly inclusive. Sides of the whorls 

 rising at right angles to the whorl within, and immediately curving ronnd the 

 deepest part with an almost circular curvature, and thence becoming slightly convex 

 as they converge towards the back, which is broad, subconvex, laterally angulated, 

 and defined on each side by an indistinct lateral groove. Suture-line, crossing the 

 sides in a deep concave curve, the ventral end of which is in advance of the 

 dorsal end, and which, after reaching the back, is bent round suddejily to form a 

 small, deep, rounded, median lobe. Margins of the mouth concave laterally, and 

 then arched forward to form a sharp overhanging ventral apex. 



8ize. — 28 mm. in length, 20 mm. in width, 9 mm. in depth. 



Locality. — Wolborough. Phillips's original specimen, as well as another smaller 

 one, is in the Museum of Practical Geology.* Mr. Vicary has five specimens ; the 



1 1832, von Bucb, ' Uber Amin. und Gon.,' p. 34, pi. i, figs. G— 8. 



2 1837, Bejrich, ' Beitr. Ehein. Ubergaugsg.,' p. 32. 



3 1851, Sandb., ' Verst. Rhein. Nassau,' p. 82, pi. vii, figs. 1—3. 



■* A large collection of Wolborough fossils, containing a certain number of Phillips's known types, 

 was long ago presented to the Museum of Practical Geology by Mr. K. Godwin- Austen. On examining 

 another of these specimens I was impressed with its likeness to a figure on one of his plates, and this 

 led Mr. Newton, Mr. ISharman, Mr. Allen, and myself carefully to examine the collection with a view 



