80 



STALK-EYED CRUSTACEA. 



basal part margmate^ the margin running for some distance along the an- 

 terior edge of the carapace ; a shglit keel runs back from the rostrum to 

 the median gastric spine. Gastric spine smaller than in G. rostrala ; anterior 

 lateral spine much longer than the posterior; there is an additional small 

 spine on each side of the carapace just behind the anterior branchial lobe. 

 Anterior half of the carapace ornamented with setiferous squamous tuber- 

 cles; on the posterior half of the carapace the tubercles assume the form of 

 interrupted transverse ridges. The median spines of the abdomen are small, 

 diminishing successively in size from the first to the third, which is obsolete 

 in many examples. Upper surface of abdomen rather hairy, the transverse 

 ridges devoid of teeth or tubercles, pleura) tuberculose, angles rounded. The 

 legs are rough with granular setose tubercles. There are two prominent 

 spines at the distal end of the carpus of the chelipeds, and one at the distal 

 end of the carpus and merus of the ambulatory limbs. The antenna? are 

 twice and a half as long as the body. 



Dimensions of a female specimen: length of body, 79 ram.; length of 

 carapace, 39 mm.; breadth of carapace, not including the lateral spines, 

 25 mm. 



This species runs into a well-marked variety in which the anterior lateral 



spines as well as the median gastric spine are very much smaller than in the 



typical form. This variety, which I have named Galacanlha diomedew^ var. 



' parvispiiia, is figured on Plate XXV,, Fig. 2. At one Station (3429) both 



forms were obtained at the same haul. 



G. diomedem differs from all other known species of Galacantha by the 

 rugose character of the sculpture on the hinder half of the carapace. In 

 the relative proportion of the anterior and posterior lateral spines it agrees 

 with G. spinom. It may be easily distinguished from G. spinosa by the 

 entirely different sculpture of the carapace, by the absence of transverse 

 rows of tubercles on the abdominal terga, etc. 



Station 3357. 782 fathoms. 1 fem, juv. 



a 



a 



a 



u 



a 



a 



u 



3363. 978 



3364. 902 

 3366. 1067 

 3371. 770 



3373. 



1877 



3393. 1020 

 3407. 885 



CC 



a 



u 



Qt 



cc 



a 



i( 



3 males, 3 fern. ovig. 

 1 fem. 



3 males, 1 fem. ovig. 

 5 males, 2 fem, (1 ovig.). 



1 male. 

 3 males. 



2 males, 1 fem. 



^ 





t 



r 



u 



m-t 



