22 Pratt, Marine Fauna of the Falkland Islands. 



widely distributed in temperate and tropical waters ; one 

 {Xantho) is cosmopolitan ; one {Paralomis) has been 

 recorded from the north and south temperate regions, but 

 not from the tropics. One {Halicarcinus) is confined to 

 the southern hemisphere ; and the distribution of one 

 {Edotia) is doubtful. 



The distribution of the genus Paralomis in northern 

 and southern temperate seas, but not in the tropics, cannot 

 be said to support Murray's view, for I do not think this 

 genus has been recorded as occurring fossil. The tendency 

 of this genus to retire into deep water might be said to 

 support Ortmann's view, but there is not much evidence 

 to turn the balance in favour of either one or the other. 



There appears to be no evidence among the repre- 

 sentatives of Crustacea in this collection of a passage 

 from one temperate zone to the other, along the west 

 coasts of America or Africa. 



TUNICATA. 



ASCIDI^ SiMPLICES. 



Boltenia legumen Lesson, Centurie Zoologique 



(1830), p. 149; Ckallenger,Yo\.Yl., Tunicata^ 



p. 88. Habitat: Falklands, and southern 



extremity of South America. 



The genus appears to be specially characteristic of 



north and south temperate seas, but has not, I think, been 



recorded from the tropics. 



Molgula gregaria Lesson = Cynthia gregaria, Cent. 

 Zoolog.,'^. 157; Challenger ^Yol.Yl., Tunicata, 

 p. 73. Habitat: Limited to Strait of Ma- 

 gellan and the Falkland Islands. It appears 

 to have been found only in shallow water. 

 The genus appears to be almost universally distributed 

 over the temperate portion of the southern hemisphere. 



