30 
THE VOYAGE OF H.M.S. CHALLENGED. 
Between Stations 264 and 265, August 24, 1875 ; Sandwich Islands to Tahiti; 
lat. 13° 15' N., long. 152° 2' W. 
Station 337, March 19, 1876 ; Tristan da Cunha to Ascension Island ; lat. 24° 38' S., 
long. 13° 36' W. 
II. Deposit shells. 
Station 120, September 9, 1873 ; off the coast of South America, between Pernam- 
buco and Bahia; lat. 8° 37' S., long. 34° 28' W.; depth, 675 fathoms ; bottom, red mud. 
Station 219, March 10, 1875 ; Admiralty Islands to Yokohama; lat. 1° 54' 0" S., 
long. 146° 39' 40" E.; depth, 150 fathoms; bottom, coral mud. 
Observations. — I have already stated that Boas has expressed doubts as to the specific 
distinctness of Limacina australis, Limacina retroversa, and Limacina trochi/ormis, and 
I have shown that Limacina australis could not be identified with either of the other 
two species. 
As concerns the latter, they have been deplorably confused by a great many authors, 
Jeffreys, 1 MacAndrew, Weinkauff, 2 A. Costa, 3 Monterosato, &c., who have attributed to 
Limacina retroversa a geographical distribution much more extensive than it really 
possesses, by crediting it with localities such as the Mediterranean, the Canaries, &c., 
which ought to refer to Limacina trochiformis alone. Limacina trochi/ormis differs 
however from Limacina retroversa (as also from Limacina australis, which belongs to 
same group), (1) in the oval form of the mouth, which is rounded anteriorly, and has the 
columellar margin recurved to the left, in contrast to Limacina retroversa where the 
mouth is quadrangular, pointed anteriorly, and with a rectilinear columellar margin ; 
(2) in the constant shortness of the spiral in proportion to its last whorl, and (3) in the 
formation of the operculum, in which the spiral portion is large in Limacina trochiformis , 
and very small in Limacina retroversa. 
# 10. Limacina bulimoides (d’Orbigny). 
1836. Atlanta bulimoides , d’Orbigny, Voyage dans l’Amerique m4ridionale, t. v. p. 179, pi. xii. 
figs. 36-38. 
1840. Sjpirialis bulimoides, Eydoux et Souleyet, Description sommaire de quelques Pteropodes 
nouveaux ou imparfaitement connus, Eevue Zoologique, t. iii. 
p. 238. 
1850. Limacina bulimoides, Gray, Catalogue of the Mollusca in the Collection of the British. 
Museum, pt. ii., Pteropoda, p. 34. 
For description and figures see Souleyet, Voyage de la Bonite, Zoologie, t. ii. p. 224, 
pi. xiii. figs. 35-42. 
1 British Conchology, vol. v. p. 116. 
2 Die Conchylien des Mittelmeeres, t. ii. p. 428. 
3 Pteropodi della fauna del Regno di Napoli, p. 19. 
