3-28 COOKE : ON THE GENUS PURPURA. 



Blainv.), in which state the tubercles are much more erect and 

 spinose, and the shell much more produced at both ends, than 

 in the adult form. 



Page 252. — '■p. nipestrisNdX. 'Voy. Venus,' t. 9, f. \=P. 

 lapilliis L. var.' 



Valenciennes' P. riipesiris lias been correctly regarded as a 

 form of striata Mart., with a somewhat patulous mouth. But 

 Tryon, not content with upsetting the received opinion without 

 a word of discussion, actually figures this very same shell (of 

 which t. 9, figs. I and i^z in the ' Venus Atlas ' obviously re- 

 present the back and front \-iews) as a Monoceros, and a synonym 

 of M. lugubre Sowb. (p. 2S5, pi. 60, f. 293) ! Who will venture 

 to explain how the front view of P. nipcstris ^"al. can be Mo/ioceros 

 lugubre Sowb., while the back view is P. lapilhis L. ? 



Page 256. — 'P. stdlaris Yiomhx. and Jacq. 'Voy. iVstr.,' 

 22, f. 13, i4=C/////(r riigosa Born.' 



This identification is open to serious doubt. The authors' 

 description of the sculpture of stellaris by no means corresponds 

 with that of any form of the variable rugosa Born. {=sacclluin 

 Chem,). To me, stellan's H. and J. looks far more like cuspidata 

 Ad. and Reeve, which latter, by the way, no one who has seen 

 the types will agree with Tryon (p. 163) in regarding as the 

 young oi pica Blainv. 



Page 256. — ' Buccinam striatum Mart. ' Univ. Conch.,' 

 pi. T^P. succinda Mart.' 



Martyn's figure of his striata, if not magnified (it is over 

 two inches in length), is certainly very near to his sucduda. But 

 the shell now generally recognised as striata Mart, is entirely 

 different from sucduda, not merely in size and in the character 

 of the ribbing and intersticial stride, but also in such an important 

 point as the dentition. I am informed by my friend, Mr. H. 

 M. Gwatkin, of St. John's College, that in the case of P. sucduda 

 the central tooth has one large notched tooth on each side, ab 



J.C, v., Jub-, 1S8S. 



