1897-98.] Prof. D’Arcy W. Thompson on Marine Faunas. 329 
deep tropical waters of both the Atlantic or the Pacific, forms 
which, if they are not intermediate between, are at least closely 
allied to the Arctic and Antarctic species. The distribution of the 
Lithodidae is, as M. Bouvier remarks, extremely curious and 
interesting, and his account merits close attention; it gives no 
support at all to a theory of bipolar distribution. 
Munidopsis Antonii, M. E. — Specimens from 1800 fathoms south- 
west of Australia, and from 1375 fathoms west of Yalparaiso, are 
identified by Henderson with the Galathodes Antonii , Milne 
Edwards, taken by the “ Talisman ” in 4000 meters off the north- 
west coast of Africa. 
Munidopsis subsquamosa, Henderson. — Described from 1875 
fathoms off Yokohama. Two specimens, one from 1450 fathoms 
off the west coast of Patagonia, and the other from }375 fathoms 
between Marion Island and the Crozets, are described as var. 
aculeata of the same species (Henderson, Chall. Rep ., Anomura, 
p. 153). A variety of striking characters in which the variety 
differs from the type species are pointed out by the describer, and 
an inspection of his figures reveals a striking difference in aspect. 
Other species of the same genus are described from Patagonia, the 
Philippines, the West Indies, the north-east coast of the United 
States, etc., and another variety of the same species is described by 
Alcock from 1800 fathoms in the Indian Ocean (. A . and M. N. H. 
(6), xiii. p. 331, 1894). Mr Faxon ( Harvard Mem., xviii. p. 86) 
considers this variety to be closely allied to M. crassa , Smith, from 
the east coast of the United States. 
More recent students of the group, for instance Bonnier (“Gala- 
theides des cotes de France,” Bull. Sc. France et Belgique (3), i., 
1888), find it necessary to describe and figure very many of the 
appendages for the identification even of the commoner European 
species. 
Mytilu-s edulis, (L.). — Eecorded from Kerguelen (Phil. Trans., 
168, p. 189), as well as from Hew Zealand, Falkland Islands, Eiver 
Plate, etc. Smith says (Chall. Rep., Lamellibranchiata, p. 272) : — ■ 
“This common species has become widely distributed, and differs 
considerably in form, colour, and size.” In the Kerguelen Eeport, 
Mr Smith says “ After a careful consideration of this species, I 
cannot arrive at any other conclusion but that the Kerguelen 
YOL. XXII. 12/98 y 
