MACRUROUS DECAPODA OF THE SUDANESE RED SEA. 391 



rostrum and the small sixth (last) tooth, which is much nearer the apex of 

 the rostrum in my specimens. The rostrum extends forward to the apex 

 of the antennnl scale and has the formula -r. All the teeth are situated on 



the rostrum and none on the carapace. This species possesses both antenna! 

 and hepatic spines on the carapace. 



Distribution. Only known from the Red Sea (Nobili) and Ternate 

 (De Man). 



Genus Anchistus, Borradaile, 1898 !>. 

 Anchistus miersi (De Man, 1888, p. 274, pi. 22. figs. 6-10). 



See Borradaile, 1917, p. 388. 



Locality. Station VII. G, 16 specimens, $ , 15-21 mm.. ? ,21-30 mm. 



Distribution. Previously recorded from the Red Sea by Nobili; Persian 

 Gulf (Nobili) ; coasts of India (Henderson), and the Mergui Archipelago 

 (De Man). 



Anchistus inermis (Mm), 1884, p. 291, pi. 32. fig. B. (PI. 27. fig. 4.) 



A. inermis, Borradaile, 1898 6, p. 387; and 1917, p. 388. 



Locality. Station VII. G, 1 <$ , 24 mm. 



Remarks. The first legs present a feature not hitherto noticed in this 

 species. The chela has the appearance of a somewhat deep spoon or scoop, 

 the edge of which is fringed with somewhat long setre (PI. 27. fig. 4). This 

 appearance is brought about by the expansion of the propodns and the 

 folding inward of its margin. This character is possibly sexual. 



Nobili (1906 a) in recording Pontonia pinna, Ortmann, from the Persian 

 Gulf, ascribes to his specimens two characters which do not agree with 

 Ortmann's original description. He says that the rostrum extends almost 

 to the end of the antennular peduncle, and that the fingers of the great 

 chela are a little longer than the half of the palm, rather more than one-third 

 of the total length of the hand. Ortmann shows the rostrum to be con- 

 siderably shorter than the antennular peduncle and, while giving no pro- 

 portions in his short description, figures the fingers of the great chela of 

 the second pair of legs as scarcely more than one-third of the length of the 

 palm. It is precisely in these two characters that Anchistus inermis, Miers, 

 differs from Pontonia pinnce, Ortmann. I think it is very probable that 

 Nobili's specimens from the Persian Gulf, recorded as Pontonia pinna, 

 Ortmann, should be referred to Anchistus inermis, Miers. There remains 

 the question as to whether Pontonia pinna, Ortmann, is really distinct 

 from Anchistus inermis, Miers. The differences between the genera lie 

 entirely in the characters of the third maxiiliped. In Anchistus, the last 



