5§ Zoological Society, 



a hybtid nor a distinct species, but merely an immature male of the 

 Tetrao Urogallus or Capercailzie, founding his opinion on the ap- 

 pearance of the Tetrao medius immediately after the re-introduction 

 of the Capercailzie into Scotland by the Earl of Breadalbane, and on 

 the fact, that no two species of a genus, however similar they may 

 be in appearance, pair voluntarily while in a state of nature. 



February 25.— R. C. Griffith, Esq., in the Chair. 



" Descriptions of six new species of Donax, in the collection of 

 Hugh Cuming, Esq. (Corf. Memb.)," by SylvanUS Hanley, Esq. 



DoNAX TiCAONicus. Dou. testd cuneiformi, convexd, nitidissimd, 

 solidd, obliqud, Icevigatd, mdxime incequilaterali, albidd, aut livido- 

 purpurascente , concolore, epidermide jiavescente indutd ; margine 

 ventrali integro, magis minusve convexo ; dorsali, antice declivi et 

 subrecto dut subretuso, postice subrecto et subitb declivi; eXtre- 

 mitate lateris antici producti, attenuatd, rotundatd ; latere postico 

 brevissimOf truncato et inferne obtuse angulato ; pube concentrice 

 et profunde rugosd ; natibus acutis, prominentibus ; superficie in- 

 ternd aut violaced aut albidd violdced postice fucatd ; dente late^ 

 rali antico remoto, postico approximato. Long. 1*; lat. 1*50 poll. 



Hab. Ticao, Philippines (Cuming). 



Remarkable for its obliquity and the abrupt truncation of the pos- 

 terior side. 



Donax culter. Don. testd elongatd, angustd, convexd, satis incequi- 

 laterali, nitidd, striulis exilibus confertim radiatd, variis coloribus 

 pictd {plerumque purpurea, sed etiam Jlavd lineis purpureo-brun- 

 neis radiatd, albidd radiis violaceis aut lividis, aurantid et rosed, 

 scepe radiis albidis ornatd) ; margine ventrali crenulato, antice sub- 

 recto, postic'h convexo ; dorsali ajitice recto et vix paululum de- 

 clivi, postice convexo sUtisque declivi ; latere antico producto, ad 

 extretnitatefyi obtuse rotundato ; postico rotundato -cuneiformi ; lu- 

 nula ligamentoqUe angustis ; pube striis simplicibus radiatd ; costd 

 umbonali obtusissimd ; dentibus later alibus haud remotis. 



Var. a. Testd subinwquilaterali ; margine ventrali medio subpostice 

 retuso; dente laterali antico, plerumque magis approximato. 



Var. b. Testd minus elongatd et magis incequilaterali ; margine ven- 

 trali raro retuso ; dente laterali antico plerumque magis remoto. 



Long. 0-50; lat. 1^50. 



Hab. Var. a. Matzellan, Gulf of California (Cuming). 

 Var. b, Acapulco (Cuming). 



Rather a common shell, and closely allied to pulchella. 



Donax asper. Don. testd trigond, ventricosd, solidd, subinceqmlate- 

 rali, albidd aut earned, antice nitidiusculd et radiatim striatd, pos- 

 tice impolitd et radiatim costellatd ; striis exilibus et simplicibus; 

 costellisparvis, decussatis, aut subsquamosis aut subgranosis, supra 

 costam umbonalem angulatam confertis ; margine ventrali crenato, 

 arcuato ; dorsali antico, valde declivi, subrecto ; postico retuso, 

 irtermi, subithque declivi : extftmitate lateris antici longioris, ro- 

 tundatd, posticd angulatd; natibus vatde prominentibus et maxime 



