1881.] 'lightning' AND 'porcupine' EXPEDITIONS. 699 



anterior side, which is scarcely one fifth the size of the other side : 

 hinge-line rectangular, occupying about one fourth of the circum- 

 ference of the shell : hinge-plate narrow : teeth in the right valve 

 short, leaf-like and V-shaped ; in the left valve laminar on each 

 side : inside poHshed, with slight longitudinal strise towards the front : 

 scars slight but large. L. 0"1, B. 0*1 125. 



'Porcupine' Exp. 1870: Atlantic, St. 24, 27, 30. 



Distribution. Bay of Biscay {' Travailleur' Exp.), G28 fms. ! 

 Algiers {Johj)\ 



M. bidentata is more elliptical and not so round, the beaks are 

 not placed so near the anterior side, and the cardinal teeth are 

 longer and more divergent, 



/^ 1. Las^a rubra, Montagu. 



Cardium rubrum, Mont. Test. Brit. p. 83, t. 27. f. 4. 



Lascea rubra, B. C. ii. p. 219, pi. v. f . 2 ; v. p. 179, pi. xxxii. 

 f. 1. 



'Porcupine' Exp. 1869: St. Donegal B. 1870: Atlantic, Vigo 

 B., Gibraltar B. 



Distribution. Apparently world-wide, from Greenland {coll. Moller 

 in Mus. Copenha(/en) to St. Paul and Amsterdam islands (Fischer), 

 in the Atlantic, and the Alaska Isles (Steariis) and Japan to the 

 Strait of Magellan {Philippi), in the Pacific; shore-628 fms. 



Fossil. Pliocene and Post-tertiary : Norway, England and Ireland, 

 and Italy ; 0-50 ft. 



Several useless synonyms. Not Kellia rubra of Goiild, which is 

 Cyamium minutum. 



M. Crosse, in a review of the second volume of ' British Conchology ' 

 (Journal de Conchyliologie, 3'' ser. t. iv. no. 2, p. 202), says that, 

 on my own showing, Lascea ought not to stand as the generic name, 

 because Brown's diagnosis was insufficient, and Leach afterwards re- 

 pudiated the name. But if a genus or species be described, although 

 incompletely, in such terms as to leave no doubt as to what was 

 meant, tlie name given to it by the describer takes precedence of 

 another subsequent name, which is accompanied by a fuller descrip- 

 tion. In the present ease, however, the subsequent description (that 

 of Recluz) is worse than the first, and is likely to mislead. Brown, 

 not Leach, was the author ; and the latter had no right to repudiate 

 or withdraw the original name without the consent of the author, 

 who actually republished it in 1844. 



2. Las^a PUMiLA, S. V. Wood. 



Kellia pumila, S. V. Wood, Crag Moll, (Biv.), p. 124, t. xii. 

 f. 15, a, b. 



'Porcupine' Exp. 1869: St. 15. 1870: Atlantic, 3,8,9, 13, 

 17a, 27, 28. 30. 



Distribution. Bay of Biscay, Sicily, and Korea ; 36-645 fms. 



Fossil. Pliocene : Coralline Crag, and Sicily. 



Monterosato proposed the generic name Zee for this shell ; but I 

 do not consider it to be generically difterent from Lasaa. At all 



45* 



