KONGL. SV. VET. AKADEMIENS IIANDLINGAK. HAND. 22. N:() 7. o 1 7 



thircl ural sugments are free. The inner ramus of the uropoJa is a tliird part a.s long as 

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

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



Colour. »Dark reddish brown, pervading whole aniuial, verging in some parts towards påle 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 fasens, J. D. 1)ANA. — United States Exploriug Expeditiou. 



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

 fig. 8. 

 " 1) » Spence Bate. 1862. Catal. Amph. Crust. Brit. Museum, 



p. 291, pl. 48, fig. 8. 

 Hypeviella fiisca, « C. Bovalijus. 1(S'S7. »Systematical list of the Ainphipoda 



Hyperiidea». Bih. t. K. Sv. Vet. 

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



Tliemistella fiisca shows a great agreement witli Th. Steenstrupi in many cliarac- 

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

 third, fourth, sixth, and seventli pairs of persEopoda, 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. Seventli segment {= telson) of abdo- 

 men separated by a suture from preceding, half narrower than the sixth. Superior antennaa 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 seventli». 



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

 pair of antenns, 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 verv narrow, first hardly apparent. Base of in- 

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

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

 Cilife of natatories about twice as long as the laniella?. Lamellai of stylets about one-third their 

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

 of lamellfe of last pair». 



