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Pseudothalestris major T. and A. Scott, has eight-jointed antennules. Pseudothalestris sarsi 

 differs distinctly from Saks' illustrations of Westwoodia minuta in the length of the joints of 

 the antennules, and in the shape and armature of the distal joint of the fifth pair of feet. The 

 expansion of the proximal joint is also much wider. 



Occurrence. — One specimen was obtained from the surface plankton collected at 

 Station 40, off Pulu Kawassang, Paternoster Islands. 



This species is named in compliment to Professor G. O. Sars whose numerous works 

 on the Crustacea are of the utmost value to every worker who attempts to study almost 

 any order of that extensive class of animals. 



Genus Eudactylopus nov. 



The body is moderately stout in front, and rather slender behind. The anterior division 

 is more or less depressed. The cephalic segment is provided with a well developed and very 

 motile rostrum. The abdomen of the female is composed of four segments. The antennules 

 are short, stout and seven-jointed. The exopodite of the antennae is two-jointed. The mandibles, 

 maxillae and maxillipedes are normal and are similar to those of the genus Dactylopusia 

 Norman. The exopodite of the first pair of feet is three-jointed, and is considerably shorter 

 than the endopodite. The terminal joint is short and armed with claws. The endopodite is 

 two-jointed or very indistinctly three-jointed. The first joint is long. The second joint is very 

 short and is armed with a very powerful claw. The exopodite and endopodite of the second, 

 third and fourth pairs of feet are three-jointed and are similar to Dactylopusia. The fifth pair 

 of feet is large, foliaceous and transparent, and completely covers the ovisac below. 



The type of the genus is Dactylopusia latipcs T. Scott (1893). It approaches Dactylo- 

 pusia in general appearance, but differs conspiciously in the two-jointed exopodite of the 

 antennae, and in the great development of the fifth pair of feet of the female. It differs from 

 Dactvlopodclla Sars (1905), in having the exopodite and endopodite of the second pair of feet 

 composed of three joints, and also in the large fifth pair. 



One species at present is known. It was represented in the material collected by the 

 'Siboga' in the Malay Archipelago. 



1. Eudactylopus latipcs (T. Scott). Plate LXIII, figs. 8 — 14. 



Dactylopus latipes T. Scott (non Boeck), 1893, p. 99, pi. X, figs. 38 — 43. 

 Dactylopusia latipes Thompson & Scott, 1903, p. 268. 



Female — length 1,4 mm. 



Seen from the side, the body appears moderately robust. The cephalic segment is large 

 and exceeds the combined length of the thoracic segments. The rostrum is well developed and 

 is very motile. 



The abdomen is composed of four segments. The genital segment is rather large and 

 is almost equal to the combined length of the second and third segments. It is marked by a 

 distinct suture traversing the middle of the dorsal surface. The second and third segments are 



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