356 Miscellaneous. 



Altai chain, and obtaining from one of them a view of the Thian- 

 Chan, whose height he estimates from 16,000 to 17,000 feet, nearly, 

 one-half being covered with eternal snows. Dr. Schrenk won for him- 

 self the proud title of being the first European who had pushed his 

 researches to the northern foot of the " celestial mountains" of the 

 Chinese empire. It is indeed quite clear, from what I already know 

 of them, that Dr. Schrenk's researches must materially change all 

 earlier maps ; for though the lake Balkash is laid down, the Issikul 

 does not appear, at least not by that name. Again, the, sources of 

 the Tchu river, and its course into the Telekul lake, and the occa- 

 sional communication between that lake and the Jaxartes (Sir Daria) ; 

 the true course of the latter stream is the country watered by the 

 upper streams of the Sara Su-a-Ishein, where alone the beautiful 

 mineral " dioptase " is found. ^-From the Anniversary Address of the 

 President of the Royal Geographical Society. 



Description of three new species of Bivalve Shells, of the genera Cy- 

 therea and Venus, by Sylvanus Hanley, Esq. 

 Cytherea Ovum. Cy. testd ovatd, solidissimd, cequivalvi, ventri' 

 cosd, nitidd, Icevigatd, albidd, epidermide fulvd indutd ; margine 

 ventrali integro, arcuato ; dorsali, utrinque convexiusculo et sub- 

 declivi; latere antico rotundato ; postico obtuse subangulato, su- 

 perne glauco-cineraceo ; natibus recte incurvatis, scepe erosis ; 

 lunuld obsoletd ; superficie internd albidd, postice livido-purpuras- 

 cente infectd ; dente postico leviter crenulato ; sinu palliari vix 

 ullo. Long. 0-90 ; lat. 1*20 poll. 

 Index Test., sup. t. 15. f. 21. Mus. Cuming, Hanley. 



Hab. ? 



Remarkable for its peculiar solidity and the equality of its sides. 

 It bears a slight resemblance to the true casta of Chemnitz, but is a 

 more ovate shell. 



Venus Bruguieri. Ven. testd oblongd, solidiusculd, subnitidd, con- 

 vexd, valde inaquilaterali, aut pallide brunned, radiis paucis albis 

 ornatd, aut fusco-cineraced, radiis saturatioribus angustis remotis 

 interruptim pictd ; radiatim sulcaid ; sulcis in medio subimbricatis, 

 utrinque subdecussatis , et postice in costellas (plerumque subgra- 

 nosas) mutatis ; margine ventrali subrecto autpaulo convexiusculo; 

 dorsali, postice vix declivi, subrecto aut convexiusculo, antic^e sub- 

 declivi et convexiusculo ; extremitate anticd rotundatd ; latere pos- 

 tico producto, obtuse et oblique biangulato ; margine postico magis 

 minusve convexo ; natibus curvatis et radio brevi livido postice 

 ornatis ; lunuld subobsoletd ; ligamento subinfosso ; margine cardi- 

 nali intus purpureo ; dentibus angustis, recurvis,parallelis. Long. 

 0-85; lat. 1*40 poll. 

 Index Test., sup. t. 15. f. 59. Mus. Cuming, Hanley. 



Hab. ? 



Belonging to the section Pullastra, and allied to decussata, but 

 easily distinguishable by its shape and peculiar sculpture. It has how- 

 ever been figured for that species in the ' Encyclopedie Methodique,' 

 pi. 283. f. 4. ' 



