Manchester Memoirs, Vol. xlii. (1898), No. 13., 19 



Strait of Magellan , 5 5 -70 fath. Between Magellan 



and Falklands. Has not been recorded from the 



Falklands before. 



Of the 4 species of this genus known : — 



I. O. vivipara is only found in the southern 



hemisphere. 

 II. O. aiistralis occurs in South Australia and 



south temperate region as well as the 



tropics. 



III. O.flaccida occurs off Bahia and off Bermudas, 



i.e., in south tropical and north temperate 

 zone. 



IV. O. pentagona occurs only in the northern 



hemisphere. 



From the preceding one may conclude that, while the 

 genus is widely distributed in temperate and tropical 

 regions, the species, though overlapping each other to a 

 certain extent, are somewhat limited in their distribution. 



Of 6 representatives of the Echinoderms in the 

 collection, 3 species are peculiar to South America, 2 of 

 which are found in the Strait of Magellan, as well as the 

 Falklands ; one is peculiar to the Falkland Islands. Two 

 species are apparently distributed over the southern 

 hemisphere, one of them extending beyond the Equator 

 to the north temperate region. 



BRACHYURA. 



{a) Catometopa. 



PiNNOTHERIDiE. 



Halicarcinus planattis White, Ann. Mag. 

 Nat. Hist., Vol. XVIII. (1846), p. 178, 

 is widely distributed over the Antarctic 

 region, and is said to be the only 

 Brachyurous Decapod proper to that wide 

 area of distribution (Stebbing, Crustacea). 



