164 ARCADE. 



This shell, known to me as a fossil only, proves to be living aliun- 

 dantly in more northern seas, and has been described in Europe 

 under the specific name buccata. It varies considerably in its pro- 

 portions, so that Moller has designated two varieties, viz., — var, 

 brevis : ovate, ventricose, lower margin strongly arcuate ; var. Icevior: 

 moderately ventricose, greenish yellow, rather smootli. It is more 

 ventricose, less elongated and more finely sulcated than L. pcrnvla. 



Leda miimta. 



Shell pear-shaped, beaks tumid, rostrum very short, scarcely upturned, and 

 squarely truncate, epidermis dusky. 



Area minuta, Fabr. Fauna Gr. 414. — Gmel. 3309. 



Area miniita Groenlandica, Chemn. Conch, x. 351, figs. 1657, 1658. 



Nucula purva, So-\vekby, Conch. 111. No. 12, fig. 7. — Reea-e, Conch. Syst. pi. 85, fig. 7, 



— Hanley, Brit. Biv. 169, pi. 19, fig. 52. 

 Nucula minuta, Philippi, Zeits. f. Malac. 101 (1844). 

 Nuruhnia minuta, Morch, Prod. Moll. Gi-renl. 21. 

 Leda minuta, Moller, Ind. Moll. Granil. 17. — Hanley, in Sowb. Thcs. iii. 114, p). 228, 



figs. 61, 62. 



Shell oblong, pyriform, tumid, beaks at anterior third, slightly 



elevated, obtuse, inclined inwards, anterior dorsal margin sloping so 



as to bring the somewhat acutely rounded point al)out midway to 



the base; posterior dorsal maroin with about the same 



Fi". 470. , 



slope as the front, direct and slightly upturned very 

 near the tip, which is very small and squarely truncate ; 

 ventral margin full and well-rounded, witli a very slight 

 emarginatioii under the tip ; dorsal face very broad, 

 with a wide, flattened, or somewhat depressed space, des- 



L. minuta. 



titute of ri])lets, in front of the beaks, and a long lance- 

 olate one defined l)y a sharp ridge behind ; disks of the valves 

 very tumid, with a shallow sub-marginal channel behind ; surface 

 deeply grooved concentrically, so as to form conspicuous reflexcd 

 riblets, which terminate on reaching the dorsal areas ; epidermis 

 dusky chestnut. Interior slightly nacreous, showing the external 

 riblets, with a very distinct shar]) ridge running from under the 

 l)eaks to the middle of the tip ; hinge witli a very small, oblique lig- 

 ament pit, with about twelve teeth before and fourteen lichind it. 

 Length, one half inch ; heiglit, three tenths of an incli : breadth, 

 one fourth of an inch. 



Sent to me in considei-able numbers from Halifax, by Mr. Willis. 



No little confusion in the synonymy of this shell, in consequence 



