4$ CRUSTACEA MALACOSTRACA. IV. 



gin. First pair of legs (fig. 2 f) moderately slender; ischium with two teeth on the inner side; merus a little 

 more than twice as long as broad, with a tooth at the end of each margin ; carpus distinctly shorter and more 

 narrow than merus, with four teeth on the inner and three on the outer margin. Second pair of legs (fig. 2 g) 

 without teeth; carpus somewhat long and moderately slender; dactylus very long, even slightly longer than 

 carpus and propodus together. Uropods (fig. 2 h) vary as to length ; the peduncle is from a little more to 

 conspicuously less than the two posterior abdominal segments combined, and its length in proportion to the 

 long endopod varies from being 7 / 4 to scarcely 6 / 4 ; the inner margin of the peduncle is coarsely serrated, 

 and some or several of the teeth are elongated, nearly spiniform, a little curved and directed much backwards, 

 while the outer margin is partly finely serrated or smooth ; the endopod is long, with the inner margin serrated 

 nearly as the peduncle and armed with 3 spines, the distal one at the end near the very long terminal spine, 

 while the outer terminal spine is very small. The exopod is somewhat shorter than the endopod. 



Length of females with the marsupium half developed 3 3.6 mm. 



Remarks. C, serratipes is in general aspect somewhat similar to C. affinis, but it is considerably 

 smaller and its appendages differ in many particulars; especially the armature of the two distal joints of 

 second maxillipeds and the serration on third to sixth joint of third maxillipeds and third to fifth joint of 

 first legs differ much in the two species ; further differences are found in the uropods, especially in the number 

 of spines on the inner margin of the endopod. The name serratipes has been chosen, because the marginal 

 serration in some pairs of appendages is more developed than in any other northern species. Sometimes 

 a proportionately somewhat low number of small dark dots may be seen on carapace and abdomen. 



Occurrence. Taken by the "Ingolf" at two stations in the warm area. 



West of Iceland: Stat. 90: Lat. 6445' N., Long. 29o6' W., 568 fath., temp. 4.4; i specimen. 



South-West of Iceland: Stat. 78: Lat.6o37' N., Long. 2752' W., 799 fath., temp. 4.5; 12 specimens. 



Family Pseudocumatidae. 



This small family comprises only two marine genera with some few species, but it has arrived at much 

 richer development in the Caspian Sea. Only one of the marine genera has been found in the "Ingolf" area, 

 but as the other genus, Pseudocuma G. O. S., goes northwards to Lofoten, Fair Isle and Scotland, it may 

 possibly occur at the Faeroes. 



Petalosarsia stebbing. 



Only a single species is known. 

 \ 



41. Petalosarsia declivis G. O. Sars. 



1865. Petalopus declivis G. O. Sars, Forh. Vidensk. Selsk. Christiania for 1864, p. 197. 

 ! 1900. Petalosarsia - G. O. Sars, Account, III, p. 77, PI. LIV. 

 1911. Stappers, Camp. Due d'Orleans, Crust. Malac. p. 121, PI. VI, figs, n 12. 



