1922.] 



vS. Kemp : Notes on Crustacea Decapoda. 



161 



does not reach the apex of the scale. It is quite straight, with 

 slightly convex upper border, and bears 9 dorsal teeth in the single 

 specimen examined. The posterior tooth is placed on the carapace 

 behind the orbit, but is not separated from the second by a greater 

 interval than that between the second and third ; the second 

 tooth is placed immediately above the posterior limit of the 

 orbit. The sixth, seventh and eighth teeth are larger than the 

 rest ; the foremost is extremely small and placed close to the 

 apex. The lower margin is strongly convex and bears a single 

 tooth situated below the penultimate of those forming the dorsal 

 series. 



There is no supra-orbital spine. The antennal spine is sharp, 

 with the hepatic placed behind it on a lower level. The eye is 

 stout, with the ocular spot touching the cornea. 



The basal segment of the antenuular peduncle (text-fig. 26a) 

 is broad ; the spine form- 

 ing the lateral process is of 

 exceptional length, reach- 

 ing as far forwards as the 

 articulation of the second 

 segment. The terminal 

 spine of the outer margin 

 is also very long, reaching 

 the base of the third seg- 

 ment. The second and 

 third segments are short 

 and broad and the fused 

 portion of the outer flagel- 

 lum is composed of only 

 four segments. The an- 

 tennal scale (text-fig 266) 

 is not quite 25 times as 

 long as wide ; the outer 

 margin is straight and ter- 

 minates in a strong tooth 

 which does not reach the 

 end of the lamella. 



The antepenultimate 

 segment of the third 

 maxilliped is somewhat 

 twisted and the ultimate 

 segment is shorter than 



the antepenultimate. The first peraeopods reach beyond the end 

 of the scale, by the length of the chela. The carpus is shorter 

 than the merus and about equal in length with the chela ; the 

 fingers are unarmed and shorter than the palm. 



The second peraeopods are unequal, the left much larger 

 than the right and reaching beyond the scale by more than 

 the length of the chela ; the two are, hov/ever, similar in structure. 

 In the larger the merus is 175 times the length of the ischium 



Text- fig. 26 

 sp. now 



a. Antennule. 



b. Antennal scale. 



Periclimenes investigator is, 



