282 THE SCHIZOPODA. 



joint oljlong-triangiilar, a little longer tlian the fiftli and finely serrate along the 

 inner margin. Tlie lower flagelliun is not fully half as long again as the upper, 

 9-jointecl, the basal joint long and extremely thickened towards the base, with a 

 large tuft of innumerable, thin sensory setae; the second joint is extremely 

 short, the third long and slender, the fourth much shorter, compressed, and 

 distinctly widened towards the end, while the five distal joints increase in length 

 to the last, all being besides strongly compressed, with the upper margin finely 

 serrate. 



The antennal squama is long, rather narrow, tapers towards the end, with 

 an outer tooth reaching beyond the short, oblique or transverse terminal margin; 

 it reaches in the male to or a little beyond the end of third joint of the antennular 

 ])eduncle (fig. 5a), in the female beyond the middle of that joint but never to its 

 end; the two distal joints of the special peduncle of the endopod (a'") are very 

 thin and taken together extremely long, reaching far behind the end of the 

 scjuaina. 



The maxillulae (fig. 5d) differ only in minor details from those of S. longi- 

 co)'ne (fig. 4a) and the same is the case with the maxillae (fig. 5e), the latter 

 being, however, proximally somewhat broader in jiroportion to the length and 

 ha^'e the fourth joint marked off at the inner margin from the lobe of thirtl 

 joint. 



Fig. 5f, representing the inner and the median lobe of the copulatory organ, 

 illustrates especially the great difference in thickness between the terminal and 

 the proximal process (p-. and p^.) which, as pointed out in the "Siboga" paper, 

 is the best specific character in this organ for S. abhrevialum in contradistinction 

 to *S'. ynaxiimon. (The coi)ulatory organ of the latter species has been figured 

 in the paper named). 



Length of a good-sized male 15 mm., of a female 'IG mm. 



Dislrihulioii. — Most of the localities enumerated in the literature are not 

 trustworthy, because the next species has frequently been confounded with S. 

 abbrerialum. Sars's type is from the tropical Atlantic, and the Copenhagen 

 Museum possesses two specimens from the same area, viz. Lat. 23° 31' N., 

 long. 22° 41' W., and Lat. 18° S., long. 2° W.; a number of specimens are at 

 hand from the area in the northern temperate Atlantic explored by the Prince 

 of Monaco. Furthermore it has been captured at some Stations in the Indian 

 Archipelago by the "Siboga." It is widely distiiliutcd in the Pacific; according 

 to the list of Stations, Expedition of 1904-H)05, it is rather conuiion in the 

 southern part in the area explored, going northwards to about Lat. 6'° S.; but 



