30 BRITISH OOLITIC AND LIASIC BRACHIOPODA. 



the front, but which only begin to rise above the level of the shell towards the anterior 

 portion, increasing as they approach the frontal margin ; beak large, more or less 

 recurved, with lateral ridges continued along the side of the valve, without recurving, to 

 join the hinge-margin, forming a defined marginal area; beak slightly compressed and 

 keeled, truncated by an entire foramen of moderate size ; deltidium in two pieces, more or 

 less hid by the recurving of the beak ; loop free, attached merely to the crural base, and 

 extending to near the internal frontal margin ; valves finely punctuated, and strongly 

 marked by numerous lines of growth. Dimensions and form variable, length 20, width 

 13, depth 12 lines. 



Obs. When treating of Ter. quadrifida, I expressed how intimately I believed it was 

 connected with the present form, and stated what distinctions could be brought forward to 

 characterise both ; it is a very common shell in the middle Lias, both of England and 

 France, found abundantly at South Petherton, and near Cheltenham, where it varies con- 

 siderably in form, as may be seen from the illustration, Plate III, figs. 17, 18. The 

 usual type approaching more or less to figs. 13, 16, and 21 ; 11, 14, 15 being exceptional 

 forms. The largest specimen I have seen in England, measuring 21 lines in length and 

 18 in breadth, belongs to the collection of the British Museum. We are indebted to 

 Mr. Moore for the working oat of the fine interior illustrating this species. 



23. Teeebratula Edwardsti, Dav. Plate VI, figs. 11, 13, 14, and 15? 



Diagnosis. Shell inequivalved, globose, more or less circular, as wide as long, straight 

 in front ; valves convex, sometimes globose, and distinctly emarginated ; beak much 

 recurved, and truncated by a small foramen advancing over the umbo, almost touching it, 

 so as to conceal the deltidium, which is rarely visible ; lateral ridges extending along the 

 sides of the shell, without recurving to join the hinge margin ; surface smooth, finely 

 punctuated; loop extending to near the margin of the shell, and simply attached to 

 Crura. Length 15, width 13, depth 10 lines. 



Obs. This species may be distinguished from both T. ptmctata and subpunctata by 

 the shortness and squareness of its shape, as well as by its strongly recurved beak, lateral 

 ridges, smaller foramen, and length of loop, which last fact is due to Mr. Moore's exertions, 

 who, after much trouble, was enabled to clear the process, seemingly identical with that of 

 T. cornuta, to which shell it approaches by many characters, though quite distinct by the 

 roundness of its sides and square front; in some specimens, as in T subpunctata, we 

 perceive a flatness at the umbo, see figs. 11 and \\a, due to compression when young. 

 Ter. Edwardsii is found along with Ter. subpunctata, cornuta resupinata, &c, in the marl- 

 stone of South Petherton, near Ilminster, and it gratifies me highly to name it after the 

 learned Dean of the French Academy of Sciences. It is with hesitation I have placed 

 here a solitary specimen, Plate VI, fig. 15, the shape of which is doubtless due to deformity. 

 Fig. 11, in Mr. Walton's collection ; 11—16, from that of Mr. Moore. 



