EEPOET ON THE SCHIZOPODA. 133 



Habitat. — The three specimens in the collection were taken at the surface of the sea 

 in the two following localities : — 



In the year 1876 I took a few specimens of the same species in the Mediterranean at 

 Messina. 



Hence it would seem to have a rather extensive distribution, the above-mentioned 

 localities lying in widely distant tracts of the ocean. 



35. Nematocelis tenella, G. 0. Sars (PI. XXV. figs. 5, 7). 



Nematoseelis tenella, G. 0. Sars, Preliminary Notices on the Challenger Schiopoda, No. 33. 



Specific Characters. — Form of body very slender and elongate. Carapace with a well 

 marked, though small, lateral denticle behind the middle of the inferior margin ; anterior 

 part slightly keeled above ; rostral projection rather narrow, straight, acuminate. Caudal 

 segments smooth above, with very small rounded epimera. Last segment rather elongate, 

 preanal spine exceedingly minute. Eyes not very large, subclavate, cornea compara- 

 tively small and' narrow. Antennular peduncle slender and elongate. Antennal scale 

 not projecting beyond second joint of antennular peduncle, very narrow, linear, apex 

 obtusely truncate. First pair of legs, when fully extended, much shorter than body, 

 meral joint scarcely projecting beyond antennular peduncle, propodal joint longer than 

 carpal, terminal joint sublinear, with only four spines. Gills comparatively simple in 

 structure, with short papillar lobules. Length 10 mm. 



Remarks. — The specimens of this form, contained in the collection, have much the 

 appearance of immature animals, but will not, in my judgment, admit of being referred 

 to either of the two species described above, since the carapace has in all of them a 

 well-marked lateral denticle, totally absent in the former. Moreover, several other 

 characters would seem to warrant the specific difference of the present form. 



Description. — None of the specimens exceed a length of 10 mm., and all have the 

 appearance of being females. 



The form of the body (see PI. XXV. fig. 5) is exceedingly slender and elongate, 

 nearly cylindrical throughout. 



The carapace exhibits a form rather simdar to that in Nematoseelis microps, Ijut 

 differs in having on either side a well-marked, though somewhat small, lateral denticle, 



