208 [February, 



base of the fore-wings, with a structure along the sub-costal nervure 

 like an Archimedean screw or diaphragm in the tracheae, especially at 

 the dilated base of the wing." 



I have examined the female Ageronia Feronia, and find the super- 

 ficies of the wings that overlap of considerable dimensions. On the 

 surface of the hind-wing the costal vein is elevated, indurated, black, 

 curved, and bare of scales for about 3'", and at first sight remarkably 

 smooth and glossy. But if this apparent smoothness be observed 

 obliquely with a strong magnifying power, in bright daylight, parallel 

 indentations or slight stride are seen all along its surface ; and under 

 the microscope these develop into a fine file or lima. When the 

 wings are expanded, this costal vein is received into a little concavity 

 in the inflated, rounded, smooth anal vein of the fore-wing, beneath 

 and near its base, which can be traced, after the fore-wing has been 

 detached, by the depression its great prominence leaves in the mem- 

 brane adjacent. This concavity is suited in every way to act as a 

 clasp, sonorous when the wings are moved, while the whole adjust- 

 ment presents, in elementary form (if we overlook a slight divergence 

 as regards correspondence of the veins), the bristle and catch that 

 lock the wings of Heterocera. 



Guildford : Jan., 1877. 



Stridulation in the genus Vanessa. — Mr. Swinton's remarks (E. M. M., xiii 

 169) on this subject are very interesting, and I wish that observations of a similar 

 character were oftener made and recorded. It seems to me, however, that the object 

 of the stridulation will bear a different interpretation from what Mr. Swinton has 

 given it. If it belonged to the class of " phenomena of rivalry and love," the me- 

 chanism would surely be more developed in the male than in the female, but it is 

 very much the reverse. I rather think tliat the object of it is intimidation of any 

 possible enemy, and that the sound should be put in the same category as the hiss 

 of a snake or the warning note of an angry wasp or bee. As it is on the female for 

 the most jiart that the perpetuation of the race depends, she will have greater need 

 for protection, and hence the greater development of the apparatus. — F. Buchanan 

 White, Perth: January loth, 1877. 



Stridulation in Vanessa Antiopa.— Mr. A. II. Swinton's article in this month's 

 Magazine, p. 1G9, reminds me that the power of stridulation exists in J'anessa- 

 Antiopa. In 1872, a female Antiopa came into my possession, in a hibernating con- 

 dition, and in that state she would, when disturbed, partially expand her wings, and, 

 at the same time, was produced a grating sound, which seemed to come from the 

 base of tlie wings. — A. II. Jones, Shrublauds, Eltham : dth January, 1877- 



