22 SCHIZOPODA. 



EUPHAUSIA MULLERI, Claus. 



1868. Euphausia Mullen, Glaus, "Einige Schizopoden und niedere 



Malacostraken Messina's," Zeits. f. wiss. Zool. vol. xiii. p. 442, 



pi. xxviii. figs. 29-31, pi. xxix. figs. 1-34. 

 1882. Thysanopoda Uclentata, G. O. Sars, " Oversigt Norges Crns- 



taceer, i. Podoplitbalma &c.," Christ. Vidensk.-Selsk. Forhandl. 



p. 52, pi. i. tigs. 16-18. 



As in a previous publication A. M. N. gave characters of 

 the then known British Schizopoda, it may be well here to 

 add a description of Euphausia and its species, which is taken 

 for the most part from Sars. But Dr. H. J. Hansen has 

 just published a paper (Bull, du Mus. Oce'anographique de 

 Monaco, No. 42, July 1905) which throws much light on the 

 genus Euphausia, and therefore the name E. Mullen is here 

 employed, and not E. pellucida. 



"JEuphausia. Carapace with antero-lateral angles but 

 slightly produced ; rostral projection, as a rule, small. Tail 

 powerfully developed. Eyes of normal structure. An- 

 tennular peduncle alike in both sexes, cylindrical, basal joint 

 sometimes provided at the end superiorly with a small lappet; 

 both flagella elongate and consisting of numerous joints. 

 Second maxillae with terminal joint very broad, exognath 

 comparatively small. First pair of legs nearly similar in 

 structure to maxillipeds and succeeding legs, save that the 

 terminal joint is somewhat expanded and armed with a fascicle 

 of short spines. The last two pairs of legs are quite rudi- 

 mentary, being present only as a minute setiferous process. " 



These are the main characters. The genus is distinguished 

 from Nyctiphanes chiefly in having the last two pairs of legs 

 quite rudimentary, whereas in Nyctiphanes only the last }tir 

 are rudimentary ; the penultimate pair being developed, but 

 having the outer joints confluent. 



The following specific characters of Euphausia Mullen 

 are the most important : Carapace distinctly keeled on its 

 anterior portion, terminating in a sharp-pointed rostrum 

 which reaches to the middle of the basal joint of the 

 antennules. Sides of the carapace bearing two pairs of 

 spines near the lower margin. Antennules bearing a small 

 lappet which is straight or slightly convex distally, and deeply 

 pectinate with several (6-8) setiform denticles, its outer angle 

 is produced into a narrow process with about three similar 

 denticles. No spine over the base of the telson ; below there 

 is a prseanal spine which is pectinated. Teison extending 

 beyond the uropods ; the lateral spine processes very strong, 

 and finely denticulated on the inner edge. 



