92 CRUSTACEA MALACOSTRACA. 



the Canary Isles (Hansen). Ortmann enumerates it from the waters near Hawaii, but to judge from 

 a preliminary examination of material from the Pacific I am inclined to think that the animals from 

 this ocean must be referred to a hitherto unnamed species. As it is not present in the older though 

 very large material in the Copenhagen Museum, which was all taken practically near the surface in 

 the Atlantic etc., I believe we may conclude that it as a rule does not approach the surface, but 

 according to the "Thor's" catches it must sometimes occur in depths between ca. 75 and 25 fm. 



9. Stylocheiron maximum n. sp. 



Description. While studying a rich material of "Stylocheiron abbrcviatum G. O. Sars" from 

 the Atlantic, the Indian Ocean and the Pacific, I discovered that it comprised two allied but very 

 distinct species, one of which was 5. chelifer Chun, while the other was either S. abbreviatum G. O. 

 Sars or a species hitherto undescribed. S. abbreviatum has been established on "Challenger" specimens 

 much less than half-grown; by the aid of Sars' figures and a couple of sketches kindly drawn by 

 Dr. Caiman for me from Sars' type I arrived at the opinion that S. abbrcviatum is synonymous with 

 S. chelifer; consequently it became necessary to give the new species a name, and S. maximum was 

 chosen as appropriate. The discovery was made after the plates to this paper were finished; I will 

 therefore only point out the two most conspicuous differences between S. maximum, n. sp. and S. abbrc- 

 viatum G. O. Sars (= .X chelifer Chun), postponing a more detailed account with figures to a subse- 

 quent occasion. 



In adult and subadult specimens of S. maximum the eyes have the upper section slightly or 

 at most a little smaller than the lower; besides, the fourth and fifth abdominal segments have no median 

 dorsal tooth. In adult and subadult specimens of S. abbreviatum the eyes have their upper section 

 much smaller than the lower, and the fourth and fifth abdominal segments each a conspicuous dorsal 

 median tooth from the hind margin. In half-grown or still somewhat smaller specimens of S. abbrc- 

 viatum the abdominal armature mentioned is feebly developed, and the upper section of the eyes is pro- 

 portionately still smaller than in larger specimens; in small specimens of S\ maximum the eyes have 

 their upper section somewhat smaller as compared with the lower than in large specimens, but that 

 section is yet conspicuously larger than in the other species. 



S. maximum is even larger than S. abbreviatum; the specimen secured by the "Thor" is an 

 adult male, measuring 23-5 mm. from the end of rostrum to the tip of telson. 



Occurrence. The "Ingolf" has not taken this fine species, but it was brought home by the 

 "Thor" in 1904. 



West of the Faeroes: 61 49' N. L., i4n'W. L., Young-fish trawl with 800 m. wire out; i spec. 



Distribution. Here it may be briefly stated that I have seen specimens of S. maximum 

 both from the Atlantic and from the Indian Ocean. I am inclined to think that at least some of my 

 predecessors (for instance Ortmann) have mixed up S. maximum with the other species. 



10. Stylocheiron longicorne G. O. Sars. 



1883. Stylocheiron longicorne G. O. Sars, Forh. Vid. Selsk. Christiania for 1883, no. 7, p. 32. 

 ! 1885. G. O. Sars, Challenger Rep., Zool., Vol. XIII. p. 144, PI. XXVII, fig. 5. 



