MARINE MOLLUSCA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 119 



Scissurella euglypta, Pels. 



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

 figs. 43-45 (1903). 



Hah. — Trawl, Burdwood Bank, at 56 fathoms. Station 346. 



Only one imperfect specimen, but recognisable. 



Scissurella supraplicata, Sm. 



Scissurella supraplicata, E. A. Smith, An7i. and Mag. N.H., xvi. p. 72 (1875). 



,, „ „ Phil. Trans. Roy. Soc. London, vol. cl.vviii. p. 176, 



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



Hah. — 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. u. (Plate, figs. 2, 2a). 



Sc. testa minuta, temiissima, alba, epidermide straminea omnino contecta, depresso-efFusa, anfractibus 4, 

 apicalibus parvis, ultimo lato, supra ad periplieriam planato, i-adiatim lineis obliquis tenuibus praedito, 

 scissura angusta, profunda, infra ad basim concentric(5 trilirato, apertura ovata, intus alba, labro pertenui, 

 columella paullum incrassata, fer^ recta. 



Alt. 1, diani. 1'75 mm. 



Z/o 6. —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, dee^o, its 

 edges being carinate. {Tiixu>p6<i, honoured.) 



Section Azygobranchiata. 



Family Cyclostrematida}. 



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



C. testa penninuta, angusta sed profund(j umbiiicata, conica, alba, delicatula, anfractibus ad 5, inclusis 

 apicalibus duobus Uevibus, Cceteris arete longitudiualiter liratis, et spiraliter decussatim striatulis, numero 

 liraruni ultimi anfractus ad quadraginta, anfractilius omnibus ventrioosis, ad suturas multum impressis, 

 apertura rotunda, peristomate continuo. 



Alt. 1, diam. 1'15 mm. 



Hab.~Traw\, 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 (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 lamellge 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. sou. edin. trans., vol. xlviil, 345.) 



