Crustacea. 23 1 



Family MAUD A E. 

 Pakamithrax Pekoni. 



Paramithrax Peronii, Milne Edwards, Hist. Nat. des Crustaces, vol. i., p. 324; 

 Jacquinot aud Lucas (15, p. 10) ; Miers (17, p. 5) ; Haswell (9, p. lo). 



Two small ovigerous females of this species were obtained in 

 Adventure Bay, Tasmania. As with numerous members of the 

 Maioid Crustacea, tliese specimens are covered with algtB, sponges, 

 &c. A few dried specimens, showing considerable variation in size, 

 occur in the National collection, and from the available information 

 it appears clear that this crab is not uncommon in the shallow 

 waters of the South Australian region. 



Distribution. — "Indian Ocean" (20), "Australia" (17), "New 

 Zealand "(15). 



Family PINNOTHERID^. 



Halicaecinus planatus. 



Cancer planatus, Fabr., Ent. Syst. ii. (1793), p. 446. 



Halicareinus planatus, White, Ann. and Mag. Nat. Hist, xviii. (1846), p. 178. 



Hymenosoma planatum, Haswell, Cat. Austral. Crust. (1882), p. 114, ibique 

 citata. 



This is a very abundant and widely distributed species in the 

 Southern Hemisphere. It is subject to a considerable amount of 

 variation, but this after all is confined to comparatively narrow 

 limits. These variations and the immense area over which this 

 species is distributed has led to the existence of a number of 

 synonyms. The ' Southern Cross ' specimens are three in number, 

 males, and quite small, being barely a quarter of an inch across 

 the carapace, and were obtained at Auckland Islands in ten 

 fathoms. 



The habitat of this species seems to vary from between tidemarks, 

 rock-pools to a depth of 150 fathoms, and a bottom of sand, mud or 

 ooze. 



The National collection contains a large number of specimens 

 from various localities, showing a circumpolar distribution. 



