15 



with me in a treasured corner of ray collection. The whole of ray speci- 

 mens are males, and it was not until some years after that I became 

 acquainted with the other sex of this singular moth. It belongs, as 

 does Alypia, to the family ZygcenidcB, as we at present understand that 

 very incongruous group, and the generic imme is Hecatesia, my species 

 Jbeing H. fenestrate. The structure by which the insect is enabled to 

 produce the singular and striking sound is the thickening of the costal 

 membrane about the apical third, behind which, and nearer to the 

 center of the wing, is a rather broad vitreous space extending almost 

 to the median nerve, this space being transversely ribbed, as are the 

 bundles of eggs in some species of Ortlwptera. The antennae are thick- 

 ened at the tips into a sort of prolonged club, pointed at the extreme 

 end, and with the under side of the terminal joints horny and devoid 

 of cilia. These, striking as they would do in flight at the will of the in- 

 sect against the transverse muscles of the transparent space, cause the 

 whizzing and characteristic sound which so attracted me, and which is 

 doubtless intended as a call of love to the individual of the weaker sex, 

 who sits enthroned in the branches listening with delight to the noisy 

 homage of her many lovers. 



Another species of this most curious group is found in the southeast- 

 ern part of the province of Victoria, and was called by the late Adam 

 White H. thyridlon. I took several examples of this in the summer of 

 185G at Westernport, the females, differing in this respect to the other 

 species, being much more common than the opposite sex. In this the 

 clear space is much smaller than in H. fenestrata, the sound produced 

 by it being weaker and more closely resembling the buzzing of a bumble- 

 bee. A third species of the genus, JET. exultans, from Western Australia, 

 is figured by Boisduvaliu Trans. Linn. Soc, London, 1877, and a fourth 

 is described and figured as a native of Mexico by Mr. H. H. Druce, in 

 the Biol. Centr Amer., but of the habits of this last mentioned nothing 

 as vet is known. 



A LETTER ON ICERYA PURCHASI. 



The following letter was written June 10, 18S9, by Hon. Edwin Wil- 

 lits, Assistant Secretary of Agriculture, to Hon. Ellwood Cooper, 

 President of the California State Board of Horticulture, in response to 

 a letter from Mr. Cooper transmitting certain resolutions of the fruit- 

 growers of California. It is here published as a good summary of the 



; past work of the Division of Entomology relative to this pest, and as a 



: statement of the present condition of affairs: 



Department of Agriculture, Washington, D. C. 

 j Hon. Ellwood Cooper, 



President State Board of Horticulture, San Francisco, Cat. 

 I have the honor to acknowledge. the receipt of your letter of May 20, transmitting 

 tho petition of the fruit-growers of California in convention assembled, to the effect 



25613— Fo, 1—3 



