1922.] S. Kemp: Noles on Crustacea Decapoda. igj 



Periclimenes (Ancylocaris) denticulatus Nobili. 



1906. Periclimenes Petitihouarsi var. denficnlata, Nobili, Bull. Mus. 



Pari!; XII, p. 257. 



1907. Periclimenes Petifthounrsi var. denticulatn, Nobili, Mem. Accad. 



Sci Torino (2) I. VII, p. ^58. 



Gatavake, Polynesia. 



The species of the P. grandis group. 



The following eleven species are very elosety allied and belong 

 to what may be termed the P. grandis group. They agree (i) in the 

 possession of supra-orbital and hepatic spines, (ii) in the narrow 

 antennal scale with distal spine far outreaching the end of the 

 lamella, (iii) in the unarmed fingers of the first peraeopod, 

 and (iv) in the presence of a spine at the distal end of the merus 

 of the second peraeopod. 



The species of this group are more difficult to identify than 

 any others of the subfamily. Many of the characters depend on 

 the proportions of various segments of the legs, which are never 

 very easy to' determine and there is considerable variation within 

 the limits of a species. The proportions of the segments of the 

 second legs undergo remarkable alteration with growth, especially 

 in males, and are usually very different in adults of the two sexes. 



In view of these difficulties I have thought it best to avoid 

 the comparative method of description and, at the risk of becom- 

 ing tedious, to give a detailed account, of each of the species I 

 have examined. 



Periclimenes (Ancylocaris) agag t sp. now 



(Plate VII, fig. 9.) 



The rostrum (text-fig. 47) is slender ; it reaches to or a 

 little beyond the end of the antennal scale and is longer than the 



TEXT-FIG. 47. — Periclimenes agag, sp. now 

 Anterior part of carapace, rostrum, etc. 



carapace. At the base it is straight, but it is a little upturned in 

 its distal half. On the slightly concave upper border it bears from 

 7 to 9 teeth, nearly always 8 or 9. ' The posterior tooth is rather 



1 Of twenty-seven specimens two have 7 dorsal teeth, twelve have S and 

 thirteen have 9. 



