36 
THE VOYAGE OF H.M.S. CHALLENGER. 
Station 24, March 25, 1873 ; off Culebra Island; lat. 18° 38' 30" N., long. 65° 5' 30" 
W.; depth, 390 fathoms ; bottom, Pteropod ooze. 
Station 33, April 4, 1873 ; off Bermuda ; lat. 32° 21' 30" N., long. 64° 35' 55" W.; 
depth, 435 fathoms ; bottom, coral mud. 
Station 85, July 19, 1873 ; off Palma Island (Canaries); lat. 28° 42' N., long. 18° 6' 
W.; depth, 1125 fathoms; bottom, volcanic mud. 
Station 122, September 10, 1873 ; off the coast of South America, between Pernam- 
buco and Bahia; lat. 9° 5' S., long. 34° 50' W.; depth, 350 fathoms; bottom, red mud. 
*2. Peraclis bispinosa, n. sp. (PI. I. figs. 9, 10). 
Characters and Description. — Shell elongated, smooth on the surface, with three or 
four bulging whorls on the spiral. The suture is milled, that is to say, the face of the 
whorls turned towards the spiral, which is somewhat depressed and slightly keeled, exhibits 
transverse ridges. In consequence of the twisting these ridges come to be disposed 
radially. The aperture is very large and long ; the lip is hollowed out towards the 
suture, and bears in front of this hollowing a tooth directed outwards and towards the 
apex of the shell. Between this tooth and the excavation the margin of the aperture is 
slightly reflected inwards. The columella is prolonged into a very long rostrum which is 
straight throughout its entire length. 
Colour. — Milky-white. 
Operculum and animal unknown. 
Dimensions. — Length 7’5 mm.; maximum diameter about 6 mm. 
Observations. — I. In the specimens from deep-sea deposits (the only specimens 
known) the surface is smooth. Perhaps in the living specimens the surface may be 
reticulated as in Peraclis reticulata. 
II. It is possible that the Spirialis diversa of Monterosato 1 was based on young 
specimens of Peraclis bispinosa. The above species has not yet been described, but 
Seguenza 2 notes in regard to fossil specimens that “ Spirialis diversa ” resembles 
“ Spirialis recurvirostra ” ( Peraclis reticulata), and that it exhibits a toothed suture. 
Challenger Specimens. — Deposit shells. 
Station VIII., February 12, 1873 ; off Canary Islands ; lat. 28° 3' 15" N., 
long. 17° 27' 0" W.; depth, 620 fathoms; bottom, volcanic mud. 
Station 33, April 4, 1873 ; off Bermuda; lat. 32° 21' 30" N., long. 64° 35' 55" W.; 
depth, 435 fathoms ; bottom, coral mud. 
Station 75, July 2, 1873 ; off Fayal (Azores); lat. 38° 38' 0" N., long. 28° 28' 30" W.; 
depth, 450 fathoms ; bottom, volcanic mud. 
1 Nuova rivista delle Conchiglie mediterranee, p. 50. 
2 Studii paleontologici sulla fauna malacologica dei sedimenti pliocenici depositati a grandi profondita, p. 30. 
