REPORT ON THE CRUSTACEA MACRUEA. 



543 



Length — female, 25 mm. (1 in.); male, 13 mn 



Length, entire (female), 



,, of carapace, 



„ of pleon, 



,, of large hand, . 



,, of dactylos of large hand, 



„ of small hand, . 



,, of dactylos of small hand, 



„ of telson, 



(0-5 in.). 



11 

 14 

 13 



i 



9 



5 



3 5 



Habitat. — Off St. Vincent, Cape Verde Islands. The station is not recorded, but it was 

 probably Station 93c, at a depth of 52 fathoms, on coralline mud. 



Heller took his specimen in the Eed Sea, where probably also that was obtained 

 from which Audouin's original figure was taken. 



Off Albany Island, Cape York, a specimen was taken that only differs from the female 

 obtained at the Cape Verde Islands by having the smaller hand upon the left side ; the 

 larger on the right side being broken off. Beyond this I see nothing either in form or 

 arrangement of parts that distinguishes it from the Atlantic and Red Sea forms. 



Alplieus avarus, Fabricius, 1 appears to have no strongly marked feature separating it 

 from Alplieus edwardsii, and I think we shall not be far wrong in saying that Alplieus 

 edwardsii, Audouin, Alplieus avarus, Fabricius, Alplieus strenuus, Dana, Alplieus parvi- 

 rostris, Dana, and Alplieus pacificus, Dana, are merely varieties of a cosmopolitan species 

 which have arisen by local selection. Dana considers Alplieus leviusculus to be only a 

 variety of Alplieus edwardsii. 



Mr. Edward J. Miers, F.L.S., late of the British Museum, considers the two specimens 

 which the late Mr. Adam White named Alplieus doris and Alplieus neptunus to be 

 respectively Alplieus edwardsii and Alplieus strenuus, but they correspond very closely 

 with Alplieus avarus of this Report and Alplieus strenuus and Alplieus parvirostris of 

 Dana. 



It moreover appears that in a genus so generally distributed as Alplieus, a specific 

 character that is largely dependent upon the form of one abnormally developed 

 appendage must be very untrustworthy as a natural distinction of species, inasmuch as 

 the tendency to vary in that organ must be great. 



1 See de Haan, in Siebold's Fauna Japonica, p. 179, pi. xlv. fig. 3. 



