152 MESSES. A. J. JUKES-BROWNE AND W. HILL : [May 1 896,. 



was not good enough for certain identification. Fortunately,, 

 however, M. Bizet was so kind as to send us two specimens of 

 P. subacutus from the Sarthe, and these enabled us to satisfy our- 

 selves that the Devon species is the same. By the same means also 

 Mr. Meyer has been able to identify a specimen in his collection. 

 We have not seen it from any other locality, and it is another of 

 the links which connect the Devon beds with the Cenomanian of 

 the Sarthe. 



Pecten, sp. 



A species occurs in the Cenomanian of Prance, and also in the 

 highest greensand of Warminster, which we have not been able to 

 identify. It bears a certain resemblance to P. Baulinianus of the 

 Gault, and appears under that name in some lists, but the ornamen- 

 tation is really very different. The shell bears a large number of 

 narrow ribs, nearly straight, but of unequal size, smaller ribs being 

 frequently, but not constantly, developed between those of normal 

 size. Each rib bears a number of strong, triangular, spinous 

 processes, arranged longitudinally, and projecting almost vertically 

 upwards. Some of the smaller ribs bear similar but more slender 

 spines, and some are nearly smooth. There are no striae on the 

 interspaces. The ears are not preserved on the few specimens that 

 we have examined. We are not sure that it occurs in Devon, though 

 some badly-preserved specimens resemble it. 



Lima simplex, d'Orb., ' Pal. Pr. Terr. CreV vol. iii. p. 545, pi. 418, 

 • figs/ 5-7. 



In the lower and most fossiliferous part of the Devon zone of Am- 

 monites Mantelli there are several large, smooth species of Lima, and 

 having obtained a specimen of Lima simplex from the Cenomanian 

 of Vimoutiers, we find that one of the Devon species bears a close 

 resemblance to it. It is large, compressed, and smooth over the 

 greater part of the shell, but has a few narrow grooves on the 

 anterior and posterior sides of each valve, which produce a sort of 

 false ribbing on these portions of the shell. 



Lima Hoperi, d'Orb. (non Sow.), and Lima Calypso, d'Orb. 



D'Orbigny's figure of Lima Hoperi has led to some confusion, for 

 it is certainly not the Lima Hoperi of Sowerby and Mantell, which 

 is common in the Upper Chalk (Senonien) of England, especially in 

 the Margate Chalk. Assuming d'Orbigny's figure to be that of an 

 adult specimen, it is much smaller, more compressed, and orna- 

 mented all over by shallow pitted grooves; whereas the true 

 Ij. Hoperi is a large shell, more inflated, and smooth, except over 

 narrow spaces on the anterior and posterior sides of each valve, 

 which have a few faint grooves. 



In the Cenomanian of Devon there is a Lima which somewhat 

 resembles the shell figured by d'Orbigny as L. Hoperi, but it is 

 more inflated, and has a deeper and more irregular set of pitted 

 grooves over the greater part of the shell. This may be the Lima 



