— 11 — 



g. Thysanopoda egregia, n. sp. 



(Figs. 20-21.) 



Description. — A single spécimen, an adult maie, is at 

 hand. Carapace rather similar to that of T. insignis, but yet 

 differing in several particulars. The gastro-hepatic groove is 



deep and long; somewhat in advance 

 of it a subvertical latéral groove is 

 seen, but this is not connected with 

 the gastro-hepatic one by any longitu- 

 dinal groove, as is the case in the pre- 

 ceding form. The submarginal furrow 

 extends forwards nearly to the front 

 margin of the carapace; the longitu- 

 dinal furrow considerably above the 

 latéral margin is nearly as in the former 

 species. Seen from above, the front 

 end of carapace between the eye-stalks 

 is nearly straight ; seen from the side 

 the dorsal outline is curved downwards 

 in front and without any process ; the 

 dorsal crest between the front end and 

 the gastro-hepatic groove is very con- 

 spicuous but yet lower than in T. insig- 

 Eyes and eye-stalks not very différent from those 



Fig. 20. - Front part of an 

 adult maie, from above. 



nis. 



in the last-named form, but the tubercle is marked off at the 



exopod is in reality only a kind of long flat process from the outer distal 

 part of first lobe, while an exopod is wanting. It has been shown by Sars 

 that in a certain larval stage a real exopod is présent (Sars, Pl. xxx, fig. i3), 

 while the plate from first joint is wanting (in larvae of the same stage ï hâve 

 been able to see that this real exopod originates from the outer margin of 

 third joint) ; in a following stage this exopod is still présent, but the plate 

 from first lobe is also already rather well developed (Sars, Pl. xxx, fig. i5) ; 

 in the folloving stage the exopod has disappeared, and the plate has been 

 furnished with marginal setse. It must be added that Sars interprets the real 

 exopod as « the larval exognath », the secondary plate from first lobe as 

 « the true exognath », but it is easily seen that this interprétation must be 

 incorrect. 



