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Thysanoëssa gregaria, G. O. Sars 



Localities. — Stat. 171 5, 22 spécimens (together with i3 

 spécimens of T. par va); stat. 1760, 1 spécimen; stat. 1849, 

 1 spécimen. 



Remarks. — This species seems to be rare in the area 

 explored, wherefore I give a new, complète list of the localities. 



Genus NEMATOSCELIS, G. O. Sars 



At présent I am acquainted with three species from the 

 Atlantic, viz. N. megalops, G. O. S., N. microps, G. O. S. (includ- 

 ing N* mantis, Chun, and N. rostrata,G. O. S., as synonyms) 

 and N. lenella, G. O. Sars; only the two first-named forms have 

 been dealt with in my former paper. N. megalops is omitted 

 here, but the two other species must be mentioned. 



Nematoscelis microps, G. O. Sars 



Of this species I have now seen more than 25o spécimens 

 taken during 1904; besîdes I have examined a good number 

 captured by the Siboga. In my former paper the main diffé- 

 rences as to latéral denticles on the carapace and shape of 

 rostrum in adult females, subadult females, adult maies, and 

 young or very young spécimens have been pointed out; some 

 further particulars are to be mentioned presently. 



In very small spécimens measuring 6-8 mm in length the 

 upper section of the eyes is much smaller than the lower part, 

 but the eyes are quite black as in the adults; a little behind the 

 rostrum the mesial line of the carapace is rather suddenly 

 raised at the dorsal organ as a short keel (N. rostrata, G. O. S.), 

 and the rostrum is a very long triangle with the base broad. 

 In about half-grown spécimens that upper section of the eyes 

 is somewhat or a little smaller than the lower part; in rather 

 large or full-grown spécimens the upper section is slightly i 



