284 



Messrs. J. Wood-Mason and A. Alcock on 



Aristevs coralinus, A. M.-Edw. in ' Challenger ' Macrura, 1 888, pi. xxxii. 

 fig. 10, cJ , antennal scale. 



An adult male and an adolescent male with commencing 

 process of the antennal scale, and an adult female, from 

 Station 115, 188 to 220 fathoms. 



Colour in life deep crimson. 



Two males and a very fine full-grown female had been 

 taken off Port Blair in 271 fathoms, and a young specimen in 

 the Gulf of Manaar in 597 fathoms. 



Our specimens of the female agree absolutely with Johnson's 

 admirable description. 



Adult males present some remarkable sexual differences ; 

 not only is their rostrum short and porrect, not extending 

 beyond the apex of the antennulary peduncles, but their 

 antennal scale is prolonged at the apex into a slender cylin- 

 drical fleshy process as long as the scale itself. This process, 



Fig-. 8. 



Aristceopsis Echcardsiana, S , X \. 



which is an extension of the thickening of the tissues seen in 

 Aristceus virilis and others, is longitudinally grooved dor- 

 sally and is of uniform width from near the base to the blunt 

 apex. 



With growth the rostrum of the female also undergoes 

 considerable reduction in length ; but it always exceeds the 

 antennulary peduncle. 



