90 



2. Astaeilla arietina, (*. 0. Sars. 



(PI. XXXVII, fig. 1.) 

 Astaeilla arietina, G. 0. Savs. Ovei-sigt af Norges Crastaceer I, p. 62, PI. 2, fig. 2. 



Specific Characters. — Very like the preceding species as to the general 

 form of the body, and the structure of the several appendages, but differing in 

 the strange development of some of the dorsal tubercles, those of the cephalon 

 assuming the appearance of a pair of very conspicuous, acute horns pointing 

 slightly forwards, and somewhat divergent. Middle segment of mesosome not quite 

 twice as long as the preceding })art of the body, and exhibiting in its anterior 

 part, dorsally, 4 remarkably strong pyramidal prominences, disposed in pairs ; the 

 posterior part of the segment very rough, owing to the presence of numerous 

 obtuse tubercles. Colour greyish, with irregular dark brown patches. Length of 

 adult female 19 mm. 



Remarks. — This form is very closely allied to A. longicomis, and I have 

 indeed been in some doubt as to whether it should not more properly be regarded 

 as a more accidental variety of that species. But, on going through the vast material 

 of A. longicomis at my disposal, I have failed to detect any sign of the peculiar 

 development of the dorsal tubercles characteristic of the present species. 



Occurrence. — The only place where this form has come under my no- 

 tice, is Tjernagel in the outer part of the Hardanger Fjord. From a depth of 

 60 to 100 fathoms, stony bottom, I there took up in the dredge 2 adult specimens, 

 female and male, the former with the inferior antenna? densely clothed with 

 the adhering newly-hatched brood. The male had much the same appearance 

 as that of A. longicomis, though the tubercles of the cephalon were quite con- 

 spicuous, whereas in the male of A. longicomis they are always wholly absent. 



3. Astaeilla affinis, Gr. 0. Sars. 



(PL XXXVII, fig. 2.) 



Archirus affinis, 6. 0. Sars, Nye Dybvandscvustaceer fra Lofoten. Chr. Vid. Selsk. Forh. 1869 , 



p. 163. 



Specific Characters. — Body of female comparatively less slender than in 

 the 2 preceding species, and but slightly tubercular. Middle segment of mesosome 

 not nearly twice as long as the preceding part of the body, and exhibiting, quite 

 in front, 2 juxtaposed dorsal tubercles of somewhat larger size than the others. 

 Eyes comparatively smaller than in the 2 preceding species. Superior antennae 

 witli the flagellum twice as long as the 2 preceding joints combined, and carrying 

 only 5 olfactory filaments. Inferior antennae with the flagellum not attaining 1 / 3 



