148 Rev. Canon A. M. Norman on BntisJi Mysidge. 



two-jointed — first joint very large, spined, 

 second minute ; nail strong. Tarsus of 

 remaining five feet multiarticulate. An- 

 teunal scale ovate, shorter tlian peduncle of 

 antenna?. Pleopocls simple in both sexes . . HeteromysiiKB. 



b. First legs not unlike the folio-wing in general 



character. Male -with all the pleopods greatly 

 developed and adapted for swimming, second 

 to fifth pairs biramose, all branches multi- 

 articulate and setose, the outer branch of 

 fourth and sometimes also of third modified 

 for sexual purposes, but the modification only 

 extending to a slight lengthening of the hmb 

 and a change in the character of the setae of 

 the terminal joints Lcjytomy since . 



c. First legs not unlike the following in general 



character. Male with first, second, and fifth* 

 pleopods as in female ; third consisting of a 

 basal joint and two short branches f ; fourth 

 of basal joint and two branches, inner minute, 

 outer styliform and generally of great length. Mysince. 



d. First legs not unlike the following in general 



character. Male with first, second, and fifth 

 pleopods as in female, third and fourth with 

 a basal joint and tw-o branches, the inner 

 minute, one-joiuted, the outer in both pairs 

 styliform, but longer in fourth than in third. . Stilomysinm (not 



British). 

 Genus Stilomysis, gen. nov. : 

 type Mysix yrandis, Goes, = Mysideis grandis, G. O. Sars. 



2. Pleopods of male all rudimentary, as in female. 

 Maxillipeds strongly built, differing widely in cha- 

 racter from those of other Mysidpe : last joint with- 

 out setfe, terminating in a very long spine and 

 three or more shorter spines. Gnathopods re- 

 sembling in tfeneral character the following legs. MysidelUnce (nol 



British). 

 Genu'< Mysidella, G. O. Sars J. 



* Hemimysis is an exception ; in it the fifth pleopods are greatly deve- 

 loped into swimming-organs, and consist of a large basal joint and two 

 multiarticulate strongly setose branches. 



t But Neomysis and Diamysis, Czerniavsky (type Mysis hahirensis, 

 G. O. Sars), have third pleopod simple, as in female. 



X I have brought Stilomysis and Mysidella into this table, because 

 those genera may occur in our seas. 



