SHIZOPOD.^. 53 



objects, I am iiu'liiunl to consider these as identical, it may 

 be observed, tliat neither show the natatory division of tlie 

 members, which from the j^reat transparency of the ani- 

 mal, their position, and not being suspected, wholly escaped 

 observation ; what streng^thens the probability of their 

 identity, is, that those obtained by the author were found 

 in the track necessarily pursued by Sir Joseph Banks to- 

 wards Rio Janicro, viz. between the Latitudes of 5° 25* S. 

 and 29°30' N. and West Long;. 17° l& and 32° 55, on the 6tli 

 12th and 25th September, where they were in considerable 

 abundance, widely distributed, and uniform in character. 



The Nocticula Banksii or Luminous Shrimp, resembles in 

 figure the animals of the Genus IMysis described in the for- 

 mer Memoir, as they do also in structure, and particularly in 

 the number and formation of the members, which consist of 

 eiglit pair, and which, on due investigation will no doubt be 

 found cleft or divided into two branches as in Mysis, so that 

 was it not for the very different construction of the sub-ab - 

 dominal fins, it would merge in that Genus ; this peculiarity 

 however, is undoubtedly generic, and argues a somewhat 

 different mode of life and means of rearing their young, 

 w^hicli last, is probably effected after the same manner as 

 we witness in the true Shrimps, where tlie ova arc appended 

 to the sub-abdominal fins, which by their great length and 

 more complete developement they arc not only fitted to 

 accomplish, but to add considerably to its power as a 

 swiuuner. As amongst the individuals taken, none presented 

 the remarkable character of the pouch of Mysis, this would 

 appear to authorize tlie opinion of Nocticula breeding 

 after a different manner, however as it would be highly 

 desirable to ascertain this point by an examination of the 

 female in the breeding season, I commissioned several 

 gentlemen going to the West Indies, to procure some/ of 

 these animals, furnishing each of them with a small hoop- 

 net, a line, and phials. One of these alone communicated 

 the result of his exertions (Major Gilland on his outward 



G 



