BRACHYUliA FKOM TOEEES STEAITS. 35 



Hyastenus spinosus, a. Milue-Edwards. 



Hyastenus spinosus, A. Milne-Edwards, N. Arch. Mus. Paris, viii. p. 250 (1872) ; Miers, Kep. 

 ' Challenger' Brachyura, p. 5G ; Alcock, Journ. Asiatic Soc. Bengal, Ixiv. (2) ]). 211 (1895). 



A female specimen, about 25 mm. in total length, agrees witli the characters of this 

 species as briefly indicated by Milne-Edwards and by Alcock, except that the lateral 

 epibranchial spines apjiear rather small. It is identical with specimens in the British 

 Museimi referred to this species by Mr. Miers. Au ovigerous female 20 mm. long 

 diflfers in possessing a small acute granule on the cardiac region and three small tubercles 

 (besides the epibranchial sj)ine) on each branchial region. Tlie two gastric spines are 

 very small, but in other respects the specimen appears to agree with this species. 



Localities. "Murray Island"; " South of Orman's reef, 5-7 fatb." 



Hyastenus oryx, A. Milne-Edwards. 



Hyastenus oryx, A. Milne-Edwards, N. Arch. Mus. Paris, viii. p. 250, pi. xiv. tig. l (1872) ; De Man, 

 Arch. Naturg. liii. p. 224, pi. vii. fig. 2 (1887) ; Alcock, Journ. Asiatic Soc. Bengal, Ixiv. (2) 

 p. 214 (1895). 



Of the two specimens which I refer to this species, one, a female about 16 mm. in 

 total length, agrees closely with the example figured by De Man, the rostral spines 

 being rather less than one-fourth of the total length and strongly divergent. In a male 

 specimen about 18 mm. long the rostral spines are more than one-third of the total length 

 and quite parallel, and the whole carapace is rather narrower and not quite so much 

 contracted in front, though still much more so than in Milne-Edwards's figure. The 

 parallel rostral spines of the latter specimen give it a certain resemblance to H. Sehcc, 

 White (Seba, Thesaurus, iii. pi. xviii. tig. 12), in which, however, the distal parts of the 

 much longer spines are divergent. In the specimens of M. Sebcc which I have examined 

 the carapace is much less tuberculated than in the present specimens. The chelipeds of 

 our male specimen resemble Milne-Edwards's figure, but the hands are rather less 

 expanded distally, and the serrated edges of the fingers meet for about half their length 

 instead of only at the tip as Alcock states. 



Locality. " South of Orman's Reef, 5-7 fath." 



Hyastenus convexus, Miers. 



Hyastenus convexus, Miers, Eep. Voy. 'Alert,' Crust, p. 19fi, pi. xviii. fig. B; Henderson, Trans. 

 Linn. Soc, (2) Zool. v. p. 344 (1893). 



A male specimen of 10 mm. and a female of 13 mm. total length are referred with 

 some douljt to Miers's species, with which they agree in the very convex gastric region and 

 in the absence of spines from the carapace. They differ chiefly in the shorter rostral 

 spines, which in the female are less than one-fourth of the total length. In the male 

 there are minute acute tubercles representing the epibranchial spines as iu the specimen 

 described by Henderson. 



LocaUtii. " Mer." 



