146 On the Australian Maioid Brachyura. 



various irregular smooth elevations on the dorsal surface ; the 

 rostrum is well developed and slightly deflexed, with tri- 

 angular-fronted cornua ; the eyes are non-retractile ; and the 

 orbit is protected above and behind by two converging spines, 

 which are separated from one another and from the upper 

 orbital margin by wide fissures ; the epistome is transverse ; 

 the external maxillipedes have the third joint expanded at its 

 external angle ; the anterior limbs (in the male) resemble 

 those of Paramithrax) and the ambulatory limbs are of mo- 

 derate length, covered with slender hairs above, and have the 

 terminal joint hooked at the apex. 



The genus Achosus is represented by at least one species 

 {A. breviceps, mihi), found in Port Jackson; and a species of 

 Oncinopus (0. angulatus, mihi) occurs both in Port Jackson 

 and in the far north. The genus Halimus is highly charac- 

 teristic of Australia in its temperate portion, at least four 

 species occurring on the coast of New South Wales and Tas- 

 mania, viz. H. tumtdus, Dana, H. spinosus, Hess (H. trunca- 

 ttpesj Miers?), H. l&vis, mihi, and //. (Microhalimus) deflexi- 

 frons, mihi. The last is distinguished from the ordinary 

 Halimi by its small size and the absence of conspicuous spines 

 on the lateral borders of the carapace. Other species of 

 Inachida3 observed in Australia are Camposcia retusa, Latr., 

 Xenocarcinus tuberculatum. White, X. depressus, Miers, Huenia 

 proteus, De Haan, II. bif areata, Streets, and Menaithius mono- 

 ceros, Latr. 



Among the Maiidas one of the most noteworthy forms is a 

 species from Torres Straits, which 1 have named Chlorinoides 

 tenuirostris, distinguished from the genus (Pseudochlorinus?) 

 represented by Chlorinus aculeatus, Milne-Edwards, C. longi- 

 spina, De Haan, and C. acanthonotus , Adams and White, by 

 the presence of a spine on the basal joint of the antennas and 

 the greater relative length and slenderness of the ambulatory 

 limbs. 



Egeria Herbstii, Milne-Edwards, and E. arachnoides, 

 Rumph., seem to replace, in Torres Straits and on the eastern 

 coast of Queensland, the Stenorhynchi and Achmi of the 

 temperate zone, and are associated with Chlorolibinia gra- 

 cilipes, Miers, a species originally obtained by H.M.S. 

 ' Herald ' from the New-Guinea coast. 



The genus Paramithrax (including Leptomithrax) is repre- 

 sented by five species, all seemingly confined to the temperate 

 zone ; these are P. barbicornis, Latr., P. sternocostulatus, 

 Milne-Edwards, P. Peronii, Milne-Edwards, Leptomithrax 

 australiensis, Miers, and L. spinulosis, mihi. 



Among the other species of this family inhabiting the Aus- 



