1879.] THE COREAN AND JAl'ANESE SEAS. 47 



whence they were obtaiued not being stated. They differ from the 

 description of P. latifrons Stimpson (Proc. Ac. Nat. Sci. Phil. p. 

 243, 18.t8), only in the following particulars. There are only two 

 spines on the lateral margins of the carapace in front of the branchial 

 regions, and one behind the outer orbital spine. The denticulations 

 of the frontal lobes are very minute, but more numerous than in 

 P. latifrons — about 9 on the median lobe and 4 on each lateral lobe ; 

 there are only two spines on the posterior margin of the carpus. 



It is possible that a larger series would show these differences are 

 not of specific importance, 



Pachycheles stevensii. 



Pachycheles stevensii, Stimpson, Proc. Ac. Nat. Sci. Phil. p. 242 

 (1858). 



Two specimens are in the collection, without definite locality 

 (male and female). This species was previously unrepresented in 

 the collection of the British Museum. Stimpson's specimens were 

 from the west coast of the island of Jesso, Japan. 



With one exception (the P. natalensis, Krauss) the only species 

 of this genus, besides the two described by Stimpson, inhabit the 

 American coasts — another indication of the affinity existing between 

 its Crustacean fauna and that of the Japanese seas, 



LiTHODIDEA. 

 Hapalogaster DENTATUS. 



Lomis dentata, De Haan, Faun. Japon., Crust, p, 219, pi. xlviii, 

 fig. 3 (1849). 



Hapalogaster dentatus, Stimpson, Proc. Ac. Nat. Sci. Phil, 

 p. 245 (1858). 



A single specimen, female, in mutilated condition, was collected 

 at the Goto Islands at low-water mark. It agrees well with a speci- 

 men from Simoda, presented to the British Museum by the Smith- 

 sonian Institution. 



This species belongs to a genus which, having a boreal range, is 

 found on the west coast of the American continent as well as on the 

 shores of Eastern Asia. An allied species, H. inert ensii, has been 

 described by Brandt from Sitka, and a third, H. cavicauda, by 

 Stimpson from California. 



Cryptolithodes expansus, sp. n. 



The species which I have thus designated is represented only by a 

 single small specimen in dried condition. The carapace is trans- 

 versely oval, with the lateral wing-like expansions broadly rounded, 

 the surface everywhere minutely punctulated. The rostrum is 

 scarcely at all deflexed, truncated, and but very obscurely triden- 

 tate at its distal end. There is a convexity upon the gastric, and 

 one more prominent upon the cardiac region, on either side of which 

 is a less elevated tubercle, the three forming a transverse series. A 

 longitudinal median ridge extends from the gastric prominence 



