KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 22. N:0 7. 317 



third ural sugments are free. The inner ramus of the uropoda is a third part as long as 

 the peduncle; the outer ramus is as long as the inner. The telson is triangular, broader 

 than, and more than a fourth part as long as, the peduncle of the last pair of uropoda. 



Colour. »Dark reddish brown, pervading whole animal, verging in some parts towards pale red- 

 dish. » (Dana.) 



Length. »Two lines». (Dana.) 



Hab. The tropical region of the Atlantic, Lat, 1° S, Long. 17° to 18° W. (Dana.) 



Syn. 1852. Lestrigonus fuscus, J. D. DANA. United States Exploring Expedition. 



Crustacea. Vol. 2, p. 983, pi. 67, 

 fig. 8. 

 » » » Spence Bate. 1862. Catal. Amph. Crust. Brit. Museum, 



p. 291, pi. 48, fig. 8. 

 Hyperiella fusca, » C. Bovallius. 1887. "Systematical list of the Amphipoda 



Hyperiidea». Bih. t. K. Sv. Vet. 

 Akad. Handl. Bd. 11. N.-o 16, p. 20. 



Themistella fusca shows a great agreement with Th. Steenstrupi in many charac- 

 teristics and in general form of body, but differs decidedly in the relative length of the 

 third, fourth, sixth, and seventh pairs of pera?opoda, in the angular hind corners of the 

 pleonal segments, and in the characteristics of the urus and its appendages. 



Dana's original diagnosis runs: 



»Thorax seven-jointed, first segment nearly concealed. Seventh segment (= telson) of abdo- 

 men separated by a suture from preceding, half narrower than the sixth. Superior antenna? as long 

 as the body, inferior one-fourth longer, inferior apex of basal portion acute. Coxa of six posterior 

 feet obtuse at apex, and claw less than half the tarsus (= metacarpus) in length. Feet of fifth pair 

 longer than sixth or sevenths. 



J o v 



The characteristic » inferior apex of basal portion)) refers probably only to the first 

 pair of antenna?, and is most likely the same feature as is described above in the second 

 and third flagellar joints of Themistella Steenstrupi. The characteristic »coxa of six poste- 

 rior feet obtuse at apex» is valid also for the preceding species. 



Dana gave further the following description of the species: 



^Greatest height of head about twice its length, rounded in front, but profile slightly flattened 

 about the antennary area. Segments of thorax all very narrow, first hardly apparent. Base of in- 

 ferior antennas having the last joint longest. Claw of six posterior legs not half as long as preceding 

 joint: coxa about as long as width of thorax; fifth joint rather longer than either of the preceding. 

 Cilia? of natatories about twice as long as the lamella?. Lamella? of stylets about one-third their 

 whole length, subcultriform, acute. Second pair of stylets extend about as far backward as middle 

 of lamella? of last pair». 



