NOTES, CAPTURES, ETC. 113 



3ellow is rej)laced by pure white, is of" very great interest. The 

 primitive colour of white flowers is supposed to have been yellow, 

 and the prevalence of these two colours in tlie Cruciferic shows 

 their close relationship. The white Pieris rapes is occasionally 

 yellow, and P. oleracea has a yellow aberration of its form venosa 

 on the Pacific slope of North America. Further, white pigments 

 may sometimes be turned yellow by the action of a caustic alkali. 

 All these things seem to me to point to the conclusion that as the 

 red of Chelonia caia is a higher form of the chrome-yellow of C. 

 villica, so the white of Pieris rapce is a more complex form of the 

 same sulphur-yellow that we see in its variety novanglice and in 

 Rumia. It is probable that the climate of Europe once resembled 

 that of North America far more closely than now, and this may 

 explain the unusual frequency of yellow forms of P. rapce in 

 America, supposing them to be atavisms induced by a return to 

 something like the old conditions, and it is worthy of remark that 

 Mr. W. H. Edwards considers venosa to be an older form than the 

 Atlantic slope P. oleracea. According to this view, the variety of 

 R. luteolata in which the yellow is replaced by white, which may 

 be conveniently called albescens, is a case of unusual metabolism 

 of a pigment which in that species normally stops short at the 

 sulphur-yellow stage. I may say, in conclusion, that I shall be 

 infinitel}^ obliged to anyone who will send me particulars (as full 

 as possible) of any variations from the normal type in insects, 

 however slight. — T. D, A. Cocicerell; West Cliff, Colorado, 

 U.S.A., January 30. 



Leioptilus lienigianus at Croydon. — As far as I can 

 ascertain, Leioptilus lienigianus has not yet been recorded as 

 occurring in Surrey. On the 18th July last I captured a specimen, 

 which was feasting on the flower of a thistle. I have since made 

 a careful search for its food-plant [Artemesia vulgaris), but am 

 unable to find it within two miles of the spot where the sjDecimen 

 occurred. As the species is endued with only a limited power of 

 flight, it therefore seems possible that there may be some other 

 pabulum. — W. G. Sheldon; Addiscombe, January 21, 1888. 



Abundance of Riiopalocera in 1887. — I have been sur- 

 prised to learn from several correspondents that they have found 

 butterflies remarkably scarce during the past season. My expe- 

 rience has been exactly the reverse, for although I took no rare 



ENTOM. — APRIL, lb88. L 



