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



Leiigtli, from tip of rostrum to tip of telson, 100 millim. ; 

 of carapace, from su])raorl>ital to posterior margin, 22'5 

 millim. ; of rostrum, from same point to apex, 26 millim. ; of 

 antennal scale 15 millim. ; of abdomen, from base to tip of 

 telson, 53"5 millim. ; of telson 14%5 millim. 



One specimen from Station 116, 405 fathoms. 

 ? juv. Differs from the above in the rostrum only extending 

 by a portion of its unarmed tip beyond the extremity of the 

 antennal scale. 



Length, from tip of rostrum to tip of telson, 58 millim. ; 

 of carapace, from supraorbital to posterior margin, 13'75 

 millim.; of rostrum, from same point to apex, 11 millim.; of 

 antennal scale 9"75 millim. ; of abdomen, from base to apex 

 of telson, 35 millim.; of telson 10 millim. 



Colour in life bright red. 



One specimen from Station 112, 561 fathoms. 

 ? jun. ]\Iuch smaller than the above, the rostrum slightly 

 ascendant, straight or only very faintly curved, short, 

 extending about lo the end of the second third of the antennal 

 scale. 



Length of carapace 10 millim.; of rostrum 5"25 millim. 



Kostrum ^-toothed. 



Colour in life dee]) crimson. 



One much younger specimen, with another of the same age 

 as that from Station 112, from Station 109, 738 fathoms. 



The above series of specimens proves that the rostrum 

 increases in hngth from extreme youth to adolescence. 



An adolescent male was taken in a previous season 8 miles 

 south-east of Cinque Island, in the Andaman Sea, in 500 

 fathoms. 



Rostrum ^-toothed. 



Colour in life deep transparent blood-red. 



41. Acant?iej)I/i/ra hrachytelsonis, Spence Bate. 



Acdnthejihijra hrachytvJsmiis, Spence Piate, ' Challoiigev ' Macrurn. 18S;S, 

 p. 7-Jo, pi. cxxvi. tig. 7, $ ; Wood-Mason, Auii."\- Mag. Nat Hist. 

 (6) vii. p. 195, cJ. 



One adolescent male from Station 113, 683 fathoms. 



Colour in life bright red. 



Two adolescent males and one young female were taken in 

 a previous sea.son 7^ miles east of North Cinque Island, in 

 the Andaman Sea, in 490 fathoms. 



Our scries of specimens proves that the rostrum undergoes 

 great changes in form and in length from youth tu maturitv. 



