242 



THE ENTOMOLOGIST S RECOED. 



the second brood of P. rapae, which, by the way, is not a very abun- 

 dant insect here, P. napi being the " common Avhite" par excellence, I 

 tried to net them both, but only succeeded in catching the pursuer. 

 On looking into my net to examine my capture, which proved to be 

 Pieris napi, I noticed a really strong and agreeable odour, remarkably 

 like that of the leaves of lemon-scented verbena {Aloijsia citrindora) 

 when bruised. This is most likely the plant Mr. C. L. Perkins 

 refers to, and not the tiowers of the garden verbena with which I have 

 compared it, but do not consider it at all similar. I then caught the 

 butterfly by the wings and smelt it, but did not notice the least trace 

 of the perfume Avhich almost immediately disappeared from the net. 

 This being my first acquaintance with the perfume, and being con- 

 nected with a male chasing a female, made me suppose that the males 

 used it to attract and please the females during courtship, and the 

 scent ceasing so suddenly suggested to me that the butterfly could 

 diffuse it at will. This little experience set me experimenting with P. 

 napi, and I find that the presence of the female is not in the least 

 necessary to make the male produce its scent, and I also think it must 

 be expelled quite involuntarily when the butterfly flaps or moves its 

 wings. The strength of the perfume varies in different individual 

 specimens, and seems much stronger in a freshly emerged one, old 

 worn males smelling more faintly. I find that, if the butterfly is taken 

 by the wings and the underside of the body smelt, hardly any trace of 

 the scent is noticed, and sometimes not at all, but if the insect is 

 taken by the thorax and the wings smelt from above and near the 

 base, it can be clearly discerned, and more powerfully if it be held 

 loosely enough for the butterfly to be able to move its wings while 

 attempting to escape. A male P. napi fluttering about in a net, and 

 so using its wings freely, emits quite a strong odour. — J. T. Bird, The 

 JNurtons, Tintern, Mon. July Sl.sf, 1905. 



^g^OTES ON LIFE-HISTORIES, LARVAE, &c. 



Ovum of ^Egeria chrysidiformis. — These flat aggi were laid singly 

 on the muslin under which the moth or moths were confined. They 

 adhered rather firmly to the muslin strands. In two cases two eggs 

 were laid side by side but not touching each other, all the rest, seventy- 

 seven, were isolated. To the unaided eye the ova appear flat, ovoid, 

 depressed on the upper surface, and almost black in colour. Under a 

 one-inch objective the eggs are seen to be very flat, with a large 

 depression, occupying the greater portion of the upper surface. The 

 walls above the depression are evenly rounded, and then run 

 perpendicularly to the base. The micropylar pole is decidedly 

 truncated, but the opposite pole is very bluntly pointed. When the 

 wall of the egg is viewed along the micropylar axis, it is seen that there 

 is a great difference in the height or depth of the two poles, the micro- 

 pylar pole being nearly O'OBmm. higher than the opposite end. The 

 following are the measurements : the long (micropylar) axis, 0-75mm ; 

 the shorter, 0-45mm. ; height (or depth) at micropylar pole, 0-3mm. ; 

 and at opposite pole 0-22mm. Colour dull, very dark grey with 

 slight purple tinge, in fact almost black. The eggshell seems 

 strong, and rather hard ; under a higher power it is seen to be 

 everyAvhere very minutely pitted on the surface. The sculpture 



