U xN I 



Plate LIV. 



Species 277. (Mus. Cuming in Bnt.) 



UnIO percoarctaTUS. Un. testa rhomboided, oblonyd, 

 compressd, epidermide fmco-uigresceuti biduld, suhrii- 

 yosd, tutus purpurea ; latere postico ohlongo, oblique 

 bianyulato, medio contracto, termino truncato, mnrgine 

 dorsali elevato, recto, margine veutrnU recto ; latere 

 antico brevissimo, subtruncato, margiue dorsali brevi, 

 recto. 



The contracted Unio. Shell rhomboidal, oblong, 

 compressed, invested with blackish-browu epidermis, 

 rather rough, purple within; posterior side oblong, 

 obliquely biangular, contracted in the middle, trun- 

 cated at the end, dorsal margin elevated, straight, 

 ventral margin straight; anterior side very short, 

 subtruncated, with dorsal margin short, straight. 



Lea, MS. in Cum. Cab. 



H„b. •? 



Tiie middle of this shell is much compressed. 



Species 278. (Mus. Sowerby.) 



L Nio Conradicus. Un. testa pared, solidd, oblongd, 

 lilted, viridi radiatd, lavigatd, intus alba ; latere pos- 

 tico oblongo, rotundatun oblique angulato, termino ba- 

 sali acuminato, margine dorsali recto, lateral iter dc- 

 clivi, margiue ventrali versus terminuin paulo smsum 

 ncclici, medio subcontraclo ; latere antico brevi, ro- 

 tuudo. 



Conrad's Unio. Shell small, solid, oblong, yellow, 

 rayed with green, smooth, white within; posterior 

 side oblong, obliquely roundly angular, basal termi- 

 nation acuminated, dorsal margin straight, laterally 

 sloping, ventral margin a little sloping upwards near 

 the end, slightly contracted in the middle ; anterior 

 side short, round. 



Lea, Trans, Amer. Phil. Soc. vol. v. t. 9. f. 33. 



Hab. ? 



Species 379. (Mus. Cuming in Brit.) 



Unio Stuarti. Un. testa oblongo-ovaU, nitidd, teuuis- 

 siiud, aureo-subviridi, intus albo-ccprulescente, dentibus 

 cardinalibus nullis, dentibus lateralibus teimibus ; la- 

 tere postico latiusculo, termino subacuminaio, obscure 

 angulato, margine dorsali recti; latere antico bred, 

 angusto, margine dorsali recto. 



Stuart's Unio. Shell oblong-oval, smooth, very thin, 

 golden-greenish, bluish-white within, cardinal teeth 

 none, lateral teeth thin ; posterior side rather wide, 

 subacnminated at the end, obscurely angular, dorsal 

 margin straight ; anterior side short, narrow, dorsal 

 margin straight. 



Adams and Axgas, Proc. Zool. Soe., 1863. 



Rab. Port Jackson. 



Species 280. (Mus. Cuming in Brit.) 



Unio plicatus. Un. testa magna, cvpansd, cuneiformi, 

 subcompressd, bialald, lavigatd, eoncentrice plicatd, 

 viridi-lnleo et castaneo eoncentrice taniatd, intus al- 

 bidd ; latere postico lata, oblique angulato, elevaiim 

 alato, inter angnlani et alum, et prupe marginem aim 

 undatim plicato, margine ventrali cunve.vo ; latere an- 

 tico brevi, alato. 



The plaited L'nio. Shell large, expanded, wedge- 

 shaped, rather compressed, with two wings, smooth, 

 concentrically plaited, concentrically banded with 

 green-yellow and chestnut, wliitish within ; posterior 

 side wide, obliquely angular, with very high wing, 

 plaited wavily between the angle and the wing, and 

 near the margin of the wing, ventral margin concave ; 

 anterior side short, winged. 



Say, Encylopa^dia Americana. 

 Unio Feruvianus, Lamarck. 

 Unio rariplicatus, Lamarck. 

 Unio Dombeianus, Valenciennes. 

 Unio undn/atus, Deshayes. 

 Unio multiplicatus, Deshayes. 



Hab. China. 



