372 



PSYCHE. 



[June 1899. 



John G. Jack, in Garden and Forest, vol. 

 X. , page 394, has given a most interest- 

 ing account of damage by this insect to 

 the willows in the Arnold Arboretum. 

 The damage there by the beetle is not 

 exceptional, for the writer has noticed 

 similar injuries in many of the larger 

 nurseries in Eastern Massachusetts. In 

 fact, some of our nurserymen are con- 

 templating abandoning entirely the cul- 



ture of poplars and willows because of 

 the damage caused by this insect. The 

 matter of remedies being still under 

 consideration the writer has recomr 

 mended so far, in the case of infested 

 shade trees, only the destruction of the 

 trees in June and a replanting with the 

 silver maple l^Acer dasycarpum) or its 

 variety, IVeirii, either of which makes a 

 good growth in damp localities. 



A GENERIC TABLE. OF THE FAMILY PANURGIDAE: A REPLY 

 TO MR. COCKERELL'S CRITIQUE ON THE SEGRE- 

 GATION OF PERDITA COCKERELL. 



BY WILLIAM H. ASHMEAD, WASHINGTON, D. C. 



In Psyche for January 1899, Mr. 

 Cockerell has made some criticisms on 

 my segregation of the genus Perdita 

 Cockerell, which seem to require a reply. 



Now, I think the whole trouble with 

 Mr. Cockerell is expressed in his 

 opening sentence : " I hardly know what 

 to say about Mr. Ashmead's three new 

 genera, established in Psyche pp. 284-285 

 at the expanse of Perdita " ; and, had he 

 waited a little longer and given himself 

 more time to investigate the subject a 

 little more thoroughly, I am convinced 

 he would have been better able to have 

 said something more to the point. 



Perdita Smith, in my paper, is not 

 defined, and the fact that Smith based 

 his genus upon a specimen without 

 maxillary and labial palpi has nothing 

 to do with the validity of the genus 

 Cockerellia. 



The genus Perdita Smith, however, 

 has been recognized, and while the 

 labial palpi do not agree exactly with 

 the imaginary figure of Smith's, there 

 is still some resemblance, and the labial 

 palpi are sufliciently different, according 

 to my views, to readily distinguish it 

 from Cockerellia ; besides the other 

 characters mentioned by Smith hold 

 good, and these, as well as other 

 differences between it and Cockerellia, 

 will be brought out in my generic table 

 given below. 



Mr. Cockerell surely must be wrong 

 when he says the male of P. hyalina or 

 albipennis has the claws simple and the 

 abdomen not banded ! I have examined 

 a great many males of this species and 

 all have the claws cleft, and the 

 abdomen banded. If Mr. Cockerell 

 possesses a specimen without these 



