Acentropus. 145 



Kolenati's figure, which he reproduced. Brown thought 

 this a distinct species. He says ''the upper and under 

 wings have different relative proportions, and the body 

 is shorter and more hairy, whilst a very definite difference 

 exists in the two blunt teeth on the hinder tibiae, of 

 which I cannot detect any trace in A. niveus." To which 

 I may add that in Kolenati's figure the cell of the hind- 

 wings is represented as open; and Kolenati, as a Tri- 

 chopterist, would naturally be supposed to pay particular 

 attention to neuration. Now Curtis's figure of Garnonsii 

 distinctly represents the hind-wings, as well as the fore- 

 wings, with a long closed cell; Westwood's wood-cut, 

 and Brown's two figures, all agree in showing a closed 

 cell in both pairs of wings. Heinemann places Acentropus 

 in the Botidce, and gives " hind-wing-cell closed,'' as one 

 of the characters of the family. Nolcken finds numerous 

 errors in Kolenati's description and figure, though I 

 cannot find that he specifically mentions the open cell. 

 Speyer (whose specimens were from the Neva) says, that 

 the wing-veins are very inaccurately figured by Kolenati ; 

 but expressly adds " the central cell of the hind-wings is 

 open : " yet he says, that Heinemann's description is 

 accurate, and that Westwood's figure agrees with his 

 specimens ! The difference between a closed cell and an 

 open cell, if constant, would be a generic, if not a familiar 

 distinction : but in truth, it is not constant, but merely 

 accidental : the closed cell is the normal form of the 

 hind-wing, and just as Kolenati and Speyer happen to 

 have alighted on a specimen in which the hind-wing-cell 

 was open, I have found one, and one only, which seems 

 to present the same aberration. With regard to the 

 different proportions of the wings, not one of Nolcken's 

 one hundred and fifty specimens from the Neva agreed 

 with Kolenati's figure; they had the same shape and 

 relative size as the specimens from the Bodensee and 

 other localities. Again, Nolcken was unable to discover 

 the two blunt teeth depicted by Kolenati on the hinder 

 tibiae of A. Nevce, and nobody else has had any better 

 success, so that I think this must be taken to be one of 

 the numerous inaccuracies of Kolenati's figures, unless, 

 indeed, Kolenati detected the spurs on the hind-tibiae, 

 and these teeth are a rough and inaccurate representation 

 of the spurs. But to pass from Kolenati's figures to his 

 own words: he says that "in Westwood's wood-cut, 

 everything agrees well with our examples " except the 



