REPORT ON THE AMPHIPODA. 1227 



of the Lsemodipoda, see Note on Desmarest, 1825 (p. 123); Latreille, 1825 (p. 125), 

 1829 (p. 138); Rurmeister, 1837 (p. 171); Milne-Edwards (Caprellines), 1838 (p. 174); 

 Milne-Edwards, 1840 (p. 184); Kroyer, 1843 (p. 202). In 1828 Zenker included this 

 group in the Leptomerse, which he made the second family of the Isopods. In 1852 Dana 

 made this group, under the name Caprellidea, the first subtribe of the Amphipoda, with 

 the two families Caprellidae and Cyamidae; see Note on Dana, 1852 (p. 256). Spence Bate 

 in 1856, drawing up his system of classification in concert with Westwood, divided the 

 Amphipoda into " Group A. Normalia," and " Group B. Aberrantia," the latter containing 

 the single family Caprellidae; in 1857 he added to this group the family Dyopedidse, 

 and in 1862 he retained the group unaltered, except that the name Dyopedidae was 

 changed into Dulichidae, and the family Caprellidae was divided into Caprellidae and 

 Cyamidae. This arrangement is also followed by Bate and Westwood in the British 

 Sessile-eyed Crustacea. Boeck in 1870 made the Caprellidae the fifth family of the 

 Gammaridas, with two subfamilies, the Caprellinae and Cyaminae ; in 1872-1876 he 

 made the Amphipoda Caprellina the third division of the Amphipoda, with the two 

 families Caprellidaj and Cyamidae. Sars in 1882 and 1885 follows this arrangement 

 with the unimportant alteration of calling the Caprellina the third tribe instead of 

 the third division. Mayer in 1882 reverts to the Lsemodipoda as the name of one of the 

 three principal groups, whether to be called subtribes or divisions, of the Amphipoda, 

 including in it the two families, the Caprellidae and Cyamidae. Cams in 1885 adopts the 

 same terminology, except that he calls the Lsemodipoda the first tribe of the Amphipoda. 

 Gerstaecker in 1886 calls the Laemodipoda the second suborder of the Amphipoda ; for 

 the definition see Note on Gerstaecker, 1886 (p. 579). Bovallius in 1886 makes the 

 Caprellidea the fifth tribe. An objection may be raised to the name Caprellina, on the 

 ground of its calling attention too exclusively to one only of the families, and that not 

 the one which embraces the oldest genus in the group, namely Cyamus, Latreille ; 

 on the other hand the term Laemodipoda has been criticised as implying an attachment 

 of the first gnathopods to the head, which is in no case actual, and in Platycyamus not 

 even apparent; there is also, I think, an advantage in having the names of the three divi- 

 sions or tribes of the Amphipoda terminating alike. 



Family Capeellidj:, White, 1847. 



Mandibles with dentate cutting edge and secondary plate ; with or without three- 

 jointed palp. 



Maxillipeds with two l pairs of plates and the palp four-jointed. 



Body narrow, more or less cylindrical ; side-plat.es often present, though 

 rudimentary. 



1 See note on Maxillipeds in the character of the tribe. 



