MARINE MOLLUSCA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 119 



Scissurella euglypta, Pels. 



Scissurella euglypta, P. Pelseneer, Voy. du S.Y. " Belgica" : Zoologie, p. 17, pi. iv. 

 figs. 43-45 (1903). 



Hob. 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). 



,, ,, Phil. Trans. Roy. Soc. London, vol. clxviii. p. 176, 



pi. ix. figs. 5, 5a (1879). 



Hob. 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 timora, 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 prsedito, 

 scissura angusta, profunda, infra ad basim concentricc trilirato, apertura ovata, intus alba, labro pertenui, 

 columella paullum incrassata, fere" recta. 



Alt. 1, diam. T75 mm. 



Hob. 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. (rifj-uapo^, honoured.) 



Section Azygobranchiata. 



Family Cyclostrematidse. 



Cyclostrema calypso, sp. n. (Plate, fig, 3). 



C. testa perminuta, anguste sed profunde" umbilicata, conica, alba, delicatula, anfractibus ad 5, inclusis 

 apicalibus duobus Isevibus, ceeteris arete 1 longitudinaliter liratis, et spiraliter decussatim striatulis, numero 

 lirarum ultimi anfractus ad quadraginta, anfractibus omnibus ventricosis, ad suturas multum impressis, 

 apertura rotunda, peristomate continue. 



Alt. 1, diam. 1'15 mm. 



Hob. Trawl, Burdwood Bank, lat. 54 25' S., long. 57 32' W., at 56 fathoms. 

 Station 346. 



Exceedingly minute, resembling C. decussatum, Pelseneer,* in many ways, but 

 differing in (a) size, and (b) 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 lamellae 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, pi. v. fig. 48 (1903). 

 (ROY. soc. EDIN. TRANS., VOL. XLVIII., 345.) 



