4 Mr. E. J. Miers on new or little-known 



or four obscure tubercles on each branchial region, and six 

 spines on each lateral margin, including the two spines which 

 represent the upper orbital margin. The spines of the ros- 

 trum are acute and strongly divergent. There is a spine at 

 the extero-distal angle of the basal antennal joint. The 

 merus joint of the outer maxillipedes is strongly produced at 

 its antero-external and the ischium joint at its antero-internal 

 angle. The anterior legs (in the male) are small ; arm with 

 a spine at the distal end of its upper margin ; wrist obliquely 

 carinated ; palm slender, smooth, and compressed ; fingers 

 straight and acute. The penultimate joints of all the ambu- 

 latory legs are dilated and almost square-truncated at their 

 distal ends, and the terminal joints strongly curved and acute. 

 Postabdominal segments (in the male) with a slight convexity 

 in the middle line. Length of female nearly 1^ inch. 



Hab. Australia (Bowerbanh). 



The legs are clothed with long fulvous hairs. 



This species is distinguished from H. aries and specimens 

 I refer to H. spinosus by the much more squarely truncated 

 joints of the ambulatory legs, from //. auritus by the exis- 

 tence of a spine on the posterior margin of the carapace, and 

 from H. tumidus by the prominent lateral marginal spines, 

 &c. In Hess's description of H. spinosus the form of the 

 penultimate joints of the ambulatory legs is not stated. If 

 the specimens now described as H. truncatipes belong to that 

 species, it will be necessary to give a distinct designation to 

 those in the Museum collection (from Victoria and King 

 George's Sound, West Australia) which are now referred to 

 H. spinosus. 



Of II. truncatipes, besides a fine female example from 

 Australia, there is a male, without definite locality, in the 

 British-Museum collection. 



Triaonotliir obtusirostris, gen. et sp. nov. 

 (PL IV. fig. 2.) 



The carapace is triangular, narrowing anteriorly, and 

 smooth ; cardiac region convex. There is a large and pro- 

 minent rounded tubercle on the cardiac region ; and the an- 

 terolateral margins, which are straight and otherwise un- 

 armed, terminate posteriorly in similar prominent lobes ; on 

 the posterior margin of the carapace are two small tubercles. 

 The very prominent rostrum is rounded above and in front, 

 and perfectly flat on its under surface ; the lateral cai'inaa are 

 acute and on a level with the flat under surface. The basal 

 antennal joint is unarmed ; and the slender flagellum is con- 

 cealed beneath the rostrum. The anterior legs (in the male) 



