REPORT ON THE PTEROPODA. 
23 
Habitat. — Antarctic Ocean, where it seems to replace Limacina helicina, between 
63' and 64° S. lat. (Eoss, under the title “ A rgonauta arctica”). 
Challenger Specimen. — Living. Station 153, February 14, 1874; in vicinity of 
Antarctic ice; lat. 65° 42' S., long. 79° 49' E. 
Observation . — The single specimen in the Challenger collection had its shell quite 
broken into small fragments. The description of the shell has been based on the unpub- 
lished figures of Hooker (1840). Two of these are reproduced on PI. I. figs. 3, 4, entirely 
on the responsibility of Hooker. 
# 5. Limacina helicoides, Jeffreys (PI. I. fig. 5). 
1877. Limacina helicoides, Jeffreys, New and peculiar Mollusca of the Family Eulimidae and 
other Families of Gastropoda as well as of the Pteropoda, procured 
on the “ Valorous ” Expedition, Ann. and Mag. Nat. Hist., ser. 4, 
vol. xix. p. 338. 
Characters and Description. — Shell smooth and shining, with a depressed, but not 
flattened spire, of three or four whorls, rounded but not expanded, with a continuous 
surface, that is to say, only separated by a slightly marked, though distinct suture. 
Aperture somewhat elongated, and angular anteriorly. Columella twisted in a 
spiral. 
Colour. — Hornv brown. 
J 
Dimensions. — Height and transverse diameter almost equal, measuring 3 ‘75 mm. 
Operculum and animal unknown. This species is perhaps in the same position as 
Limacina triacantha. 
Habitat. — Atlantic Ocean to the north of the Equator, always at the bottom, with 
the shell empty : — “ Valorous ” Expedition, Station 12 ; lat. 56° IP N., long. 37° 41' W.; 
at a depth of 1450 fathoms. “Porcupine” Expedition (1869), west of Ireland, Station 
28; lat. 56° 44' N., long. 12° 52' W.; at a depth of 1215 fathoms. “Porcupine” 
Expedition (1870), Station 17, Bay of Vigo (not Bay of Biscay as Jeffreys says 1 ); 
lat. 39° 42' N., long. 9° 43' W.; at a depth of 750 to 1095 fathoms. “ Travailleur ” 
Expedition (1800), Bay of Biscay. 2 
Challenger Specimen. — Deposit shell. 
Station 78, July 10, 1873 ; off the Azores ; lat. 37° 26' N., long. 25° 13' W.; depth, 
1000 fathoms; bottom, volcanic mud. 
1 Ann. and Mag. Nat. Hist., ser. 4, vol. xix. p. 338. 
- Jeffreys, The French Deep-Sea Exploration in the Bay of Biscay, Rep. Brit. Assoc., 1880, p. 387. 
