MARINE MOLLUSCA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 345 
Scissurella euglypta, Pels. 
Scissurella euglypta, P. Pelseneer, Voy. du S.Y. “Belgica”: Zoologie, p. 17, pl. iv. 
figs. 43-45 (1903). 
Hab.—Trawl, Burdwood Bank, at 56 fathoms. Station 346. 
Only one imperfect specimen, but recognisable. 
Scissurella supraplicata, Sm. 
Scissurella supraplicata, E. A. Smith, Ann. and Mag. N.H., xvi. p. 72 (1875). 
35 3 5 Phil. Trans, Roy. Soc. London, vol. elxvii. p. 176, 
pl. ix. figs. 5, 5a (1879). 
Hab.—Trawl, Burdwood Bank, at 56 fathoms. Station 346. 
Several examples, mostly imperfect, of this pretty species, striking on account of 
its very marked plication above the double keel. 
Scissurella tumora, sp. n. (Plate, figs. 2, 2a). 
Sc. testa minuta, tenuissima, alba, epidermide straminea omnino contecta, depresso-effusa, anfractibus 4; 
apicalibus parvis, ultimo lato, supra ad peripheriam planato, radiatim lineis obliquis tenuibus predito, 
scissura angusta, profunda, infra ad basim concentricé trilirato, apertura ovata, intus alba, labro pertenui, 
columella paullum incrassata, feré recta. 
Alt. 1, diam. 1°75 mm. 
Hab. —Station 325, Scotia Bay, South Orkneys, 9-10 fathoms, on Macrocystis 
pyrifera and other large Fuci. 
A depressed, obliquely effuse little species, of which but few examples occurred, all 
in live condition, covered with straw-coloured epidermis. The upper part of the body 
whorl is not so conspicuously radiate as in many species ; the slit is narrow, deep, its 
edges being carinate. (t:uwpds, honoured.) 
Section Azygobranchiata. 
Family Cyclostrematide. 
Cyclostrema calypso, sp. n. (Plate, fig. 3). 
C. testa perminuta, angusté sed profundé umbilicata, conica, alba, delicatula, anfractibus ad 5, inclusis 
apicalibus duobus levibus, ceteris arcté longitudinaliter liratis, et spiraliter decussatim striatulis, numero 
lirarum ultimi anfractfis ad quadraginta, anfractibus omnibus ventricosis, ad suturas multum impressis, 
apertura rotunda, peristomate continuo. 
Alt. 1, diam. 1:15 mm. 
Hab.—Trawl, Burdwood Bank, lat. 54° 25’ 8., long. 57° 32’ W., at 56 fathoms. 
Station 346. 
Exceedingly minute, resembling C. decussatum, Pelseneer,* in many ways, but 
differing in (a) size, and (6) in fine and close longitudinal liration. To C. conicum, 
Watson, collected during the Challenger Expedition (Station 24), it likewise is akin ; 
but in this species, more than double the dimensions to begin with, the lamelle are 
much stronger proportionately, and fewer in number than in either C. decussatum 
or C. calypso. 
* P. PELSENEER, Voy. du S.Y. “ Belgica,” p. 19, pl. v. fig. 48 (1908). 
