MARINE MOLLUSCA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 349 
Lacuna abyssicola, sp. n. (Plate, figs. 8, 8a, 8b). 
L. testa parva, profundé umbilicata, albo-calcarea, epidermide brunnea contecta, fragili, vix solida, 
anfractibus 5, quorum apex ipse miré immersus, duobus his proximis cum penultimis tumidulis, ultimo 
paullum effuso, levi, omnibus infra suturas canaliculatis et acute spiraliter carinatis, apud basim, circd 
umbilicum, crassi-carinato carinis binis, sulco interstitiali preedito, apertura rotunda, labro tenui, margine 
columellari laté reflexo. 
Alt. 2, lat. 2°15 mm. 
Hab.—Deposit No. 38, dredged March 18, 1904. Lat. 71° 22’S., long. 16° 34’ W., 
1410 fathoms. Station 417. 
One specimen only, but adult and fairly perfect, save for a slight fracture of the 
outer lip. It appears nearly akin to L. nautiliformis, Jeffreys, or L. concta of the same 
author, from the Atlantic, collected on the Porcupine Expedition, especially as 
regards the sculpture round the umbilical region, the thickened double carination with 
interstitial sulcus. Another feature of interest is the curiously immersed nucleus, 
and the strong canaliculation round the upper portion of each whorl, followed by an 
acute spiral keel. The substance of the shell is chalky white, covered with a dark- 
brown epidermis. ‘The specific name proposed is given in consideration of the extreme 
depth at which it was dredged. 
Lacuna wandelensis, H. Lamy. 
Lacuna wandelensis, KE. Lamy, Expéd. Antarct. Francaise commandée par le Dr Jean Charcot : 
Moil., p. 5, pl. i. figs. 5, 6, 7 (Paris, 1906). 
Hab.—Station 325, Scotia Bay, South Orkneys, 9-10 fathoms, on Macrocystis and 
other large Fuci. : 
A very few examples, and all in non-adult condition, belong almost certainly to 
this species. 
Family Rissoide. 
Rissoa deserta, Sm. 
Rissoa deserta, EK. A. Smith, Nat. Antarct. Exped.: Nat. Hist., vol. ii. p. 9, pl. i. fig. 1 
(1907). 
Hab.—South Orkney Islands, Scotia Bay, 9-10 fathoms. Station 325. 
The specimens are dead, but seem to agree in form with the above species. 
issoa (Onoba) filostria, sp. n. (Plate, fig. 9). 
R. testa parva, paullum inflata, solidula, parum rimata, anfractibus 43, quorum apicales duo leves, 
tumiduli, ceteris ventricosis, apud suturas impressis, arctissimé spiraliter tenuiliratis, apertura ovata, alba, 
labro paullum etfuso, haud multum incrassato, feré continuo. 
Long. 2, lat. 1:50 mm. 
Hab.—South Orkney Islands, Scotia Bay, 9-10 fathoms. Station 325. 
Allied to several Onobx, mostly described of recent years from deep-sea explora- 
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