CRUSTACEA MALACOSTRACA. III. 137 



Eurycope G. o. Sars. 



In his Account Sars has given a good description of the genus with eight Norwegian species. 

 From Eurycope as limited by Sars a number of species not known at Norway have now been removed 

 to Storthyngura Vanh. and Munnopsurus Rich. After their removal the remaining forms agree with 

 each other in the following features. 



The body is oval and more or less oblong, without processes. Head generally with the front area 

 sharply limited, at least on the sides. The antennulse are dorsal; first joint large, depressed, rather 

 plate-shaped; second joint somewhat small and short, inserted on the upper surface of first joint before 

 its front margin. Antennae with a distinct exopod marked off by a suture or articulation. Mandibles 

 with the cutting edge divided into teeth, the movable lacinia on left mandible well developed, some 

 setae or at least a single seta behind the lacinia, the molar process well developed, moderately to 

 very thick with the end cut off. The articulation between thorax and abdomen and that between sixth 

 and seventh segments well developed. The legs are mentioned in the diagnosis of the group; in this 

 genus fifth joint of the natatory legs is very broad, considerably or much less than twice as long as 

 broad. Median lamella of the male operculum at most very moderately narrowed at the middle. 



The material from our area comprises thirteen species, six among them described from Nor- 

 way, four have been established on species from various other seas and three are new. As some of 

 the forms unknown to Sars are more or less allied to one or another of his species, I found it useful 

 to pay attention to some features not valued or totally omitted in his descriptions, and to correct a 

 few points. Nearly all my specimens have lost most or all thoracic legs, but fortunately their shape 

 or length are not necessary for the determination, as the peduncles of antennuke and antennae, the 

 surface of the head, the maxillipeds, the uropods, and the abdominal operculum in both sexes afford a 

 number of excellent characters. 



The thirteen species may be divided into two sections in the following way. 



Sect. A. Species with all thoracic segments freely movable Species 89 to 97. 



Sect. B. Species with fifth and sixth thoracic segments completely fused, without any dorsal suture 

 between them excepting near the lateral margins Spec. 98 to 101. 



89. Eurycope Murrayi Walker. 

 (PL XII, figs. 7 a— 7 b). 



1903. Munnopsist Murrayi Walker, Ann. Mag. Nat. Hist. Ser. 7, Vol. XII, p. 227; PL XVIII, figs. 



1—6. 

 1905. Munnopsis Murrayi Tattersall, Isopoda, p. 24 and 73; PL V, fig. 8. 



191 1. Tattersall, Nord. Plankton. VI. Die uord. Isopoden, p. 190, figs. 8—14. 



1913. Muunatrycopc Tjalfiensis Stephensen, Vid. Medd. fra den naturh. Forening i Kjobenhavn, Vol. 



64, p. 99, figs. 6—8. 

 11915. Stephensen, in Rep. Danish Oceauogr. Exped. 1908—10, Vol. II, No. 



3. p. 23, figs. 12—13. 



t8 



The Ingulf* Expedition. III. $. 



