NO 5.] ACCOUNT OF THE SPECIES. 69 



Fam. pseudocalamidje.i 

 Gen. Pseudocalanus, Boeck. 



Syn: Clausia, Boeck (not Claparede). 

 „ I/ucullus, Giesbrecht. 



Remarks. This genus was established as early as in the year 1864 by 

 Boeck; but the name at that time proposed, Clausia, having been already 

 appropriated, it was subsequently changed by him to Pseudocalanus. Dr. 

 Giesbrecht did not at first recognize Boeck's genus, that named by him Lu- 

 cullus being the very same. As yet, only a single species of this genus is 

 known; for the species recorded by Boeck as Pseudocalanus armatus is 

 generically distinct, and even belongs to a different family, Mtidiidce. In the 

 samples taken during the 'Fram' Expedition, I have found 3 species referable 

 to this genus. One of them is the type species originally recorded by Boeck. 



12. Pseudocalanus elongatus, Boeck. 



Syn: ImcuUus acupes, Giesbrecht. 



This well-known form occurred not infrequently in some samples taken 

 between the 12th and 24th October, 1893, north of the New Siberian Islands. 

 It was also found occasionally in a sample taken farther north. 



Distribution. Coast of Norway, British Isles, west coast of France, 

 Kiel Bay, the Baltic. 



13. Pseudocalanus major, n. sp. 

 (PI. XX). 

 Specific Characters. Very like the type species as to external appearance, 

 but almost twice as large. Anterior division of body regularly oblong oval 

 in form, scarcely broader in front than behind, and only composed of 4 seg- 

 ments, the last one with the lateral parts rounded off behind. Tail nearly 

 half as long as the anterior division, genital segment about the length of the 

 2 succeeding ones combined, and rather protuberant below in its anterior part, 



1 The corresponding subfamily is termed by Dr. Giesbrecht Clausocalaninw from the 

 genus CloMSOcalanus; but as Pseudocalanus is of much earlier date, the name of 

 the family should, according to the rule in zoology, rather be derived from that 

 genus. 



