4i 



Terebratula coarctata natural size ; a, Dorsal view ; I, side 

 view ; c, ventral ditto ; d, an enlarged portion with the different 

 markings. 



We copy the following description of this interesting shell 

 from the annals of Natural History for 1852, Vol. IX. (second 

 series, p. 256, pi. xiv., f. 3), by Thos. Davidson, Esq., F.K.S., 

 &c. 

 TEREBATULA MOEIEREI, Deslongchamps. 



Shell inequivalve subpentagonal, longer than wide; valves 

 convex, with a deep, longtitudinal, angular sinus or depressions, 

 so that the junction of the two sinuses in front, a deep, angular 

 notch is produced ; beak rather short, recurved and truncated 

 by a largish circular entire foramen ; ridges well marked, 

 leaving between them and the hinge a well-defined space ; area 

 valves ornamented by numerous squamose concentric, projecting 

 imbricated ridges, regularly and closely covering all the surface 

 of the shell. Loop unknown most probably short. Structure 

 perforated. Length 9, width 8, depth 6 lines. , 



This curious form of Terebratula was discovered by M. Moriere, 

 at St. Honorine des Perthes, near Port-en-Bessin in Normandy, 

 in beds named by M. de Camont Calcaire marneur de Port en 

 Bessin, which according to M. Deslongchamps, correspond to the 

 inferior Oolite of Caen. This shell having been presented for 

 M. Deslongchamps' examination he at once perceived all its 

 remarkable distinctive characters and forwarded his notes and 

 illustrations (fig. 3 of our plate) requesting me to publish the 

 species, which is dedicated to M. Moriere, the discoverer. 



Terebratula Horierei cannot be confounded with any other 

 Jurassic form ; at first sight it bears some resemblance to Tere- 

 bratula coarctata, but the deep sinus in both valves and the con- 

 centric squamose ridges at once distinguish it. 



