278 



centricis reflexis, utroque laminosis, et striis crassis radiantibus 

 decussata ; decussationibus anterioribus punctatis ; umbonibus 

 elevatis, anteversis, contiguis : lunula lata, vix circumscripta : 

 latere anlico angustato, rotundato ; latere postico late et oblique 

 truncate; margine dorsali rectiusculo; cardine dentibus in dex- 

 tra valva duobus fissis, in valva sinistra dente unico fisso : intus 

 porcellana ; margine crenulato. Long. 2 ; alt. If; lat. 1^. Hob. 

 Puget Sound ; Straits of De Fuca. 



Has the form and general aspect of Saxidomus NuttaUi, Con- 

 rad, in which the hinge teeth are quite different, and there are 

 no traces of diverging lines. The sculpture is much finer than 

 in V. Domheyana^ and more like that of V. decussata. It varies 

 considerably in its size and proportions, being often much more 

 expanded. One specimen measured in length 3f ; height 2f ; 

 breadth 1^. 



Arca sobria. Testa transversa, inequilateralis, rhomboidea, 

 alba, costulis numerosis radiantibus, posticis majoribus, rugosis, 

 instructa, et undulis remotis concentricis subreticulata ; latere 

 antico angusto, rectangulari, in marginem ventralem postice 

 desinente ; latere postico oblique truncato, ad apicem acuto ; 

 umbonibus elevatis, angulatis ; area cardinali angusta lanceolata ; 

 cardo dentibus ad octo utrinque instructus. Long. | ; alt. ^^^y ; 

 lat. tV poll Hab. ? 



It has the outline of A. Deshaysii, but is much smaller, more 

 slender, more numerously ribbed, less acute posteriorly. 



Dr. C. T. Jackson read an analysis of the nevir mineral 

 Algerite, by Mr. Richard Crossley. It had been analyzed 

 before by Mr. T, S. Hunt, and described by Mr. Francis 

 Alger. For the analysis and description, see Boston Journal 

 of Natural History, Vol. VI. p. 118. 



