ON NEW BRACniOPODA. 159 



hesitation, by Mr. Davidson. It will be seen from what 

 follows tliat two species at least of Terebratella ai*e to be 

 found in these beds ; but when D'Orbigny placed the 

 Terehratula hemisphcBrica in this genus, he could not have 

 seen its interior, which, in several examples I possess, have 

 the short and simple loop of Terebratula, and the shell 

 in question will therefore have to return to its original 

 Position. 



TEEEBEATELLA. 



Terebratella Bückmanii, Woodward M.S. 



PL I., figs. 1-5. 



Shell generally a little longer than wide, rounded in 

 front, and tapering to the beak ; valves moderately convex ; 

 beak short, very slightly ineurved and truncated by a 

 foramen, surrounded in part by the extremity of the beak, 

 the umbo of the dorsal valve, and two small labral deltideal 

 plates. Internally the adult shell is provided with a doubly 

 attached loop, the first pair of lamellae extending consider- 

 ably before becoming reflected to form the loop. Sliell 

 structure punetuate. Dimensions of the largest example 

 hitherto observed : length, 3^ lines ; width, 3 lines ; dej)th, 

 1^ lines. 



Obs. — I had collected a considerable number of these 

 little brachiopods from the oolite of Hampton Cliffs, under 

 the idea that they were the young of Terebratula maxiUata, 

 my object being to prepai'e dissections shewing the loop of 

 that species. I was much interested in finding in the 

 example I first opened that it could not belong to the 

 young of that genus, although outwardly it is almost 

 undistinguishable from it. The difference in the loop 

 provcd it to be a true Terebratella. My Observation doea 

 not shew that it attained larger dimensions than those 



