— i8 — 



Especially the shape of the front part of the carapace and the 

 lobes or processes on the two proximal joints' of the antennulae 

 ought to be described more minutely and figured more correctly 

 than hitherto done. Scarcely half-grown or at least still smaller 

 spécimens show a somewhat other shape of the front part of the 

 carapace than that observed in the adults. Local variation as to 

 size of adult spécimens and as to the shape of antennular lobes 

 or processes ought to looked for. In future papers I will attempt 

 to fill up thèse defects in our knowledge as well as possible; 

 here I must confine myself to comments on some few species. 



A. Carapace with a pair of latéral marginal denticles near 

 the posterior end. 



Thysanopoda sequalis, n. sp. 



Description. — Allied to T. obtusifrons, G. O. Sars, and 

 T. vulgaris, H. J. H., but sharply distinguished by the shape of 

 the lobe from first antennular joint. — The anterior third of the 

 upper side of the carapace is adorned with a low keel which 

 terminâtes at some distance from the anterior end; slightly 

 behind this end we find a mesial excavation of some breadth, 

 and this excavation goes so far backwards that its posterior 

 portion encompasses on both sides the anterior part of the keel 

 mentioned; outside the excavation the surface is slightly raised 

 so that the impression is conveyed that two very broad and low 

 keels bound the excavation mentioned. Seen from above, the 

 front margin of the carapace is shaped nearly as in T. obtusi- 

 frons, G. O. Sars (Challenger Rep. PL xvm, fig. 2), but the 

 end does not protrude so near to the front margin of the eyes 

 as — according to the figure referred to — is the case in the 

 last-named species. Seen from the side, the front tip of the 

 carapace shows scarcely any vestige of the minute vertical tooth 

 observed in T. vulgaris. The carapace is otherwise as in T. vul- 

 garis, with the latéral denticles well developed. Eyes as in 

 T. vulgaris. The lobe from first antennular joint is large, cover- 

 ing about half of the second joint, and very peculiarly shaped. 



