On the Conservation of Species in Parasitic Crustacea. 271 



rugose-punctate, transversely impressed near the base ; centre 

 of disk with a longitudinal groove. Elytra broader than the 

 thorax, oblong, sides narrowly margined, their outer edge, to- 

 gether with the apical border, serrate ; apex rounded ; above 

 convex ; each elytron with eight rows of deep regular punctures, 

 interstices obsoletely costate. 



A single specimen, without locality, in my own collection. 



Microrhopala Sallei, n. sp. 



M. anguste ovata nigra ; thoracis vittis duabus elytrorumque vitta 

 lata humerali, a basi fere ad medium producta, postice angustata, 

 fulvis ; elytris profunda punctato-striatis, interspatiis altemis ob- 

 solete vittatis. 



Long. 2 lin. 



Hab. Guatemala, Mexico. 



Thorax transversely excavated at the base, deeply punctured, 

 a longitudinal fulvous stripe on either side, just within the 

 lateral border, continuous with the humeral patch on the elytra; 

 sides of the elytra subparallel, scarcely oval, finely toothed. 



In my own cabinet ; also sent me for examination by M. 

 Salle and Rev. H. Clark. 



.[To be continued.] 



XXXII. — On the remarkable Means by which certain Species of 



Parasitic Crustacea effect their Conservation. By M. Ecoknk 



Hesse*. 

 The object of my present paper is to call attention to the means 

 by which the conservation of their species is assured to certain 

 parasitic Crustacea, such as the TVebta, the Calipi, the Pandora, 

 and the Chumlracanthi. 



All carcinologists are aware that many of these singular ani- 

 mals, which, on their issuing from the egg, are furnished with 

 powerful instruments of locomotion, are, on the contrary, very 

 insufficiently provided with them when in the adult state, some 

 being even completely deprived of them ; that, moreover, there 

 are some to which organs of vision have been denied, sometimes 

 in the males, sometimes in the fen)ales ; so that these dis- 

 inherited creatures become perforce stationary, and are com- 

 pelled to follow the fortunes of the fishes at whose expense they 

 live. 



In this situation, so perilous to the species, it is easily con- 



• Translated by W. S. Dallas, F.L.S., from a separate impression, com- 

 municateil by the author, of his paper in the ' Me'moires des Savants 

 j^trangert.' 



