408 THE VOYAGE OF H.M.S. CHALLENGER. 



" Appendix caudalis duplo longiov quam ad basin lata, fere usque ad radicem fissa ; lacinia utraque 



in apice spinis singulis armata. 

 " Longitude animalis 10 mm." 



It can be recognised at the first glance, Metzger says, by the great sickle-sliaped finger of the 

 first peraeopod. The upper antennee are somewhat shorter than the lower. The hinder 

 edges of the three first pleon-segments are slightly crenulate, their lower angles are almost 

 rectangular, and only a little drawn out posteriorly. (The species described under the name 

 Atylus uneinahis by G. 0. Sars, in 1882, seems to be identical with Metzger's Atylus 

 falcatus. It must, I should think, belong to the genus Tritmta, Boeck, but, as unfortun- 

 ately neither description takes note of the mandibles, tlie generic position is left a little 

 uncertain.) 



The male of Bathyporeia pilosa, Lindstrom {Bathyporeia pelagka, Bate) is not rare, he says, 

 " im flaohen Wasser am Straude der Inseln und selbst im Wattenmeere (Osterems, Memmerts- 

 balge)," but with the female he has never happened to meet. (On British coasts, in the sand, 

 uncovered by the fide, I may notice that the female is far more frequent than the male.) 



He confirms the supposition that " Megamoera Alderi," Bate, is the female of Melita proxima. 

 Bate. 



Nxnia excavata, Bate, is found along with Nxnia rimapalmata. Bate, the latter the more rare. 



Siphonoecetes cuspidatus, n. s., is thus described: — " Eostrum frontale gracile, aculeiforme, paulo 

 longius quam anguli laterales capitis, oculos gerentes. AntenniB inferiores longitudine 

 animalis parum modo breviores. 



" Pedes Imi paris manu vix longiore quam carpo oblongo. 



" Pedes 2di paris manu multo longiore quam carjjo triangulari. 



" Pedes 3 et 4ti paris articulo tertio paulo longiore quam lato ; ungue longitudinem articuli 

 quarti et quinti junctorum .'equanti. 

 ' " Eamus exterior pedum saltatorius. Imi paris in margine exteriore spinis brevibus circiter 8 

 instructus, in margine interiore inermis ; ramus interior in margine exteriore spinis 3 

 armatus, in margine interiore minutissime denticulatus. 



" Pedes saltatorii ultimi paris ramo parvo rotundato, eadem fere latitudine ac longitudine. 



"Appendix caudalis spatiis binis scabridis instructa. Longitudo animalis 6 mm. 



In further description he says, among other things, " das erste Fusspaar zeigt einen ovalen, am 

 Ende abgestutzten Carpus, dessen innere Vorderecke mit einem liingern Dorn versehen ist ; 

 die Hand ist kaum so lang wie der Carpus, und der schriige Palmarrand mit zwei grosseren 

 Domen bewafi'net, zwischen welchen der an der Innenseite sagezahnige Finger einschlagt. 

 Das zweite Fusspaar ist etwas kraftiger als das erste, der dreieckigo Carpus kiirzer als die 

 Hand und an dem nach innen gerichteten Winkel mit einem kurzen aber kriiftigen Dorn 

 endend." At the first glance Metzger took it for a species of Corophium. 



1871. Sars, G. 0. 



Beskrivelse af de paa Fregatten Josephines expedition funde Cumaceer. K. 

 Svenska Vetenskaps-Akademieus Haudlingar. IX. no. 13. 1871. 



" G. O. Sars states that in several genera of Crustacea there are two sorts of males, one nearly 

 resembling, the other very different from, the females ; the former is much more common 

 and may be found all the year round, the other only in one season ; the latter may be the 

 fully developed and the former the incomplete stage of the male. This has been observed 

 in DiastyUs, Pontuporia, Apseudes, and Philomedes, and exists therefore in very difierent 

 orders." (Dr. von Martens in Zool. Kocord for 1872.) 



Compare Note on Faxon, 1884, and Note on Chilton, 1885. 



