CYAMUS. 83 



body, whilst out of several hundred Cyami preserved in 

 the collections at the Jardin des Plants he was only able 

 to detect a single individual of C. erraticus, the mode of 

 life of that species not rendering it so apparent to the 

 collector as the species which associate together in vast 

 numbers on prominent parts of the body. 



From the further observations, both of Martens and 

 Roussel de Vauzeme, it would appear that the violent 

 storms of the winter season are very destructive to the 

 Cyami, many of the parts of the whales generally in- 

 fested by them being then free ; those which survive 

 being feeble and discoloured. He only observed C. er- 

 raticus to preserve its rosy tint, but its numbers were also 

 diminished. 



The relations of the Cyami with other Edriophthalmous 

 Crustacea are very interesting. Placed by Linnaeus, 

 Pallas, and Miiller amongst the Onisci, and arranged by 

 Fabricius with the Aselli and Cymothoe, their relationship 

 with the order Isopoda was indicated ; and M. Roussel de 

 Vauzeme, the author of an elaborate memoir on the 

 genus in the " Ann ales des Sciences Naturelles" (2 e Ser. 

 vol. i.), maintained their nearer approach to the Isopods 

 than to any other Crustacea. Latreille, at first, placed 

 the genus with the Gammari, in the order Amphipoda, 

 but he subsequently united it with Caprella, to form the 

 distinct order Lcemodipoda ; nor can we doubt (notwith- 

 standing the objection of M. Roussel, founded on the 

 variations in the mode of insertion of what he terms the 

 fore legs) that this is the legitimate position of the 

 genus ; in fact, Caprella is but a laterally compressed 

 Cyamus, and but little imagination is required to con- 

 vert the former into an excessively attenuated Cyamus, so 

 perfectly similar is the disposition of the segments of the 

 body and limbs in both animals. 



G 2 



