from the Challenger Expedition, and recently Mr. G. Thomson lias made known 

 a New Zealand species, C. Icevis. On the other hand, the anomalous form de- 

 scribed by the present author from the Mediterranean as Cyclaspis cornigera 

 is scarcely congeneric, and, indeed, this form has recently been included by the 

 French zoologist Jules Bonnier, in a new genus. Cyclaspoides. The species be- 

 longing to the present genus are easily recognized by the peculiar form of the 

 carapace, the long and slender tail, and the structure of the uropoda. Only a 

 single Norwegian species is as yet known. 



4. Cyclaspis longieaudata, G. 0. Sars. 

 (PL vii & vm.) 



Cyclaspis lonyicaudata, G. 0. Sars. Om den aberrante Krebsdyrgruppe Cumacea og dens nordiske 



Arter. Chr. Vid. Selsk. Forh. 1864, p. 82. 



Specific Characters. Carapace of female very large and tumid, almost 

 globose in form, and perfectly smooth, with the upper margin boldly vaulted, 

 pseudo-rostral projection distinct, though rather short, sub-rostral incisions well 

 marked; that in adult male much less deep and more evenly vaulted above, 

 pseudo-rostral projection less prominent, antero -lateral corners blunted. 1st pedi- 

 gerous segment not visible at all; 2nd segment well developed; the 3 succeeding 

 ones narrowing abruptly. Tail exceedingly slender and elongate, much longer 

 than the anterior division, all the segments contracted in their anterior part; 

 last segment nearly as long as the preceding one, gradually widening distally, 

 and considerably produced behind. Eye wholly absent. Superior antenna; with 

 the sensory filaments of the outer flagellum extremely elongate ; those in male 

 with an additional bundle of such filaments at the base of the flagellum. Palp 

 of anterior maxillse with a single apical seta. 2nd pair of maxillipeds with the 

 basal joint unusually large, lamellar, and coarsely denticulated in the distal part 

 of the outer edge. 3rd pair of maxillipeds with the basal joint strongly developed, 

 being more than twice as long as the succeeding joints combined, and angularly 

 bent in the middle; terminal expansion very large, reaching beyond the meral 

 joint. 1st pair of legs exceeding the carapace in length, basal joint large and la- 

 mellarly expanded in the middle, terminal part very slender, with the propodal 

 joint the longest; 2nd pair longer than the succeeding pairs, and terminating in 

 4 diverging spines. Uropoda in female scarcely longer than the last segment, 

 basal part very short and perfectly smooth, rami twice the length of the former 

 and sub-equal, both terminating in a sharp point, the inner one without spines or 

 setse ; those in adult male considerably more slender, basal part much longer 



