HANSEN: ON SIX SPECIES OF KOENENIA. 



apical whorl of glabrous setae is found on the first, the second, 

 the third, the fifth and the seventh, but not, as in the two pre- 

 ceding species, also on the ninth joint; the setse in these whorls 

 are only half as long as in the preceding 

 species and more slender; the shape of the 

 basal part of the joints and the division into 

 subjoints are as in A', mirabilis with the ex- 

 ception of the reductions accompanying the 

 loss of a subapical whorl on the ninth joint. 

 The two last joints are comparatively short; 

 the apical has only one whorl of very long, 

 pubescent setœ, and it terminates in one very 

 long seta. The flagellum of K. Grassii I 

 am only acquainted with from a drawing 

 kindly sent me by Dr. Silvestri and inserted 

 here. We see that it contains only nine 

 joints, that a subapical whorl of strong and 

 comparatively long glabrous setae is found on 

 the same five joints as in K. chilcnsis^ while 

 the fourth, the sixth and the eighth joints 

 possess a subapical whorl of much shorter 

 setae which are conspiuously longer than in 

 K. WJiccleri. Furthermore the terminal joint 

 possesses two whorls as in K. mirabilis. 

 The flagellum looks very robust. 



One of the specimens of K. angusta had 

 a defective flagellum with five joints (pi. 4, fig. i e) still preserved. 

 It exhibits a curious anomaly: the third joint is coalesced with the 

 fourth and quite misshapen: of the subapical whorl only some 

 few set^e are seen on the lower side, and the submedian whorl 

 on the fourth joint is also imperfect. The joints preserved are 

 short and very robust, their plumose setse shorter than in K. 

 mirabilis and K. Wheeleri, the division between the main joint 

 and the subjoint with the glabrous setœ can not be discerned 

 with certainty in the first joint but is plainly observed in the 

 others, and of the four setas on the basal subjoint the two lower 

 ones are more than twice as long as the upper ones. • — In one 

 specimen of K. siamaisis the basal joint is preserved (pi. 4, 



19 



Fig. I . Kocnenia Grassii, 

 Flaeellum. 



