240 MR. E. J. MIERS ON THE OXYSTOMATOUS CRUSTACEA. 



seven broad, triangular, nearly equal teeth. Anterior legs slender; arm granu- 

 lous and rounded on its anterior and inferior and the proximal half of its posterior 

 margins ; wrist and hand smooth ; hand slightly compressed, but scarcely carinated. 

 Sab. Australia, Moreton Bay. 



In both N. plicata and N. abbreviata the anterior legs are smooth, the arm trigonous, 

 and the hand angulated and carinated. In N. plicata the teeth of the posterolateral 

 margins are unequal ; in N. abbreviata they are nearly obsolete. 



2. Nursia plicata ? (Plate XXXVIII. fig. 28.) 



? Cancer plicatus, Herbst, Naturg. Krabben u. Krebse, iii. pi. lix. fig. 2 (1803). 



Nursia hardwickii, Leach, Zool. Miscell. iii. p. 20 (1817) ; M.-Edw. Hist. Nat. Crust, ii. p. 137 (1837). 



Nursia plicata, Bell, Trans. Linn. Soc. xxi. p. 307 (1855), no figure. 



Hob. Indian Ocean. 



Mr. Bell observes of this species, that the only specimens with which he was acquainted 

 (those in the British-Museum collection) were brought from India by General Hard- 

 wicke. He evidently was unaware of the true habitat of the specimens of N. plicata, 

 and confounded them with N. hardwickii. These specimens were in the collection 

 in 1852, three years prior to the date of the publication of Mr. Bell's essay ; and one of 

 them is undoubtedly figured by him as JV. plicatus (pi. xxxiv. fig. 4). In the British- 

 Museum copy of Herbst's work the description and plate containing the figure of his 

 Cancer plicatus are unfortunately wanting ; and therefore I cannot tell to which of the 

 undoubtedly distinct species, JV. sinuata and iV. hardwickii, it is to be referred. V. 

 hardwickii of all ages is distinguished from the N. sinuata by the anterior legs, which 

 are flat, smooth on the upper surface, with the anterior and posterior margins of the 

 arms thin and sharp-edged, not rounded, as in 2V. sinuata. 



The specimen I have figured is the typical example of N. hardivickii. 



Arcania, Leach. 

 Ae.ca.nia granulosa, sp. n. (Plate XXXVIII. fig. 29.) Carapace shining, subglobose, 

 uniformly and distinctly granulated, with ten short, acute, equidistant, smooth 

 marginal spines — and one on the intestinal region, above the two posterior marginal 

 spines. The frontal spines short, projecting but slightly over the eyes. Anterior 

 legs slender, about twice as long as the carapace ; arm distinctly, wrist and hand 

 very finely granulated. Length nearly f in. ; breadth £ inch. 

 Sab. Australia, Moreton Bay. 



This species is distinguished by the granulated carapace (which is not at all tubercu- 

 late or spinulose on its upper surface) from the other species of the genus. 



Cryptocnemtjs, Stimpson. 



This genus was established by Stimpson in 1858 for a Crustacean discovered in Japan, 

 and remarkable for the extension of the carapace laterally over the ambulatory legs, to 

 which he applied the specific name of C. pentagonus. A second species, C. grandidierii, 

 was described by M. A. Milne-Edwards in 1865, from Zanzibar. 



