490 MESSRS. BAIRD AND ADAMS ON CHINESE SHELLS. [May 9, 



lection, there are several species which deserve some special notice, 

 besides two or three which appear to be undescribed. 



1st. Unio douglasice. In 1833 Dr. Gray shortly described and 

 accurately figured, in the twelfth volume of Griffith's edition of Cu- 

 vier's ' Animal Kingdom,' a species of Unio which he calls Uiiio 

 douglasi(E. The type specimen of this shell has always been, and 

 still remains, in the collection of shells in the British Museum. Dr. 

 Lamprey has brought a considerable series of this Unio, which seems 

 to be not uncommon in the neighbourhood of Shanghai. Perhaps 

 from not knowing the shell as figured in Griffith, JNIr. Lea some 

 years afterwards described and figured a species from China, which 

 he named Vnio murchisonianus, but which, there is no doubt, is the 

 same as the U. douglasicB of Gray. Still later, in the seventh volume 

 of his 'Observations on the genus Vnio' he describes and figures a 

 species from Shanghai, which he calls V. shanghaiensis. A careful, 

 examination of the description and figures of the two last-named 

 species, with the type specimen of that described and figured by Dr. 

 Gray in Griffith's 'Animal Kingdom,' satisfies us that the three 

 species are identical. The name IJ. douglasice must therefore stand, 

 having the precedence over the others by some years, 



2nd. Anodonta tenuis. Another species of the family Unionidce,\ 

 brought by Dr. Lamprey, appears to be the U. tenuis of Gray, 

 figured also in Griffith's 'Animal Kingdom.' In the list of the 

 figures of shells at the end of the twelfth volume of that work this' 

 shell appears twice, first under the name of Anodon tenuis, and 

 secondly under that of Unio tenuis. An examination of the speci- 

 mens brought by Dr. Lamprey shows that this species belongs more 

 correctly to the genus Anodonta than to Unio, as no trace ot teeth is 

 to be seen in it. A reference to the figure will also demonstrate this; 

 and this shell, therefore, though denominated in the plate Unio tenuis, 

 must be now, as indicated in the letterpress, called Anodonta tenuis. 

 From there being uo lengthened diagnosis given with the figures, 

 these two last-named species are but little known under their original 

 names. 



3rd. Glauconomya primeana 1 Two apparently distinct species of 

 Glauconomya are in the collection of Dr. Lamprey. One of these ap- 

 pears to resemble somewhat the G. chinensis of Gray ; and the other 

 more nearly approaches to one lately described and figured in the 

 third volume of the third series of the ' Journal Conchyhologique,' 

 by jNIM. Crosse and Debeaux, under the name of G. primeana. 

 Several specimens of these shells occur ; and it is possible they may. 

 all be referred to this species, though they differ in some respects 

 from the figure given in the above-mentioned work. 



4th. Anodonta gihha. A very interesting series also occurs of the 

 Anodonta gihba of Cantor and Benson, which show^s how consider- 

 ably this species varies according to age. When adult it is much 

 more rounded, and appears shorter than the younger specimens. 



5th. Nanina ravida. A very interesting series of a species of 

 Nanina was also brought by Dr. Lamprey. Several specimens un- 

 doubtedly represent the Nanina ravida of Benson, have a tolerably 



