No. 115.] 115 



Thk Hop-vink Aphis. 

 Phorodon humuli (Scbrank). 



The following notice of the above-named insect was sent to the 

 editor of the Watervllle Times, of Waterville, N. Y., under date 

 of July 19, 1886, in response to a note of inquiry from him : 



Dear Sir. — Yours of the sixth instant, making inquiry of the 

 hop aphis, accompanied with specimens of the leaves of the hop 

 covered with " honey-dew," was duly received. Your communi- 

 cation states : 



I send you by this mail a box containing hop leaves, upon which 

 you will find honey-dew, lice and black flies (said to be the English 

 aphis and breeders of the lice). Vines all over the State are 

 covered with this sort of vermin. Lice appeared about June 

 fifteenth, and have increased steadily since. For the benefit of my 

 numerous hop readers 1 would like to have your ideas on them, 

 briefly or at length, as to origin, nature, life, and connection with 

 honey-dew. 



I regret that I cannot possibly, in consideration of my other 

 engagements, give you at this time a full notice of this insect pest, 

 such as I would like to send you. It would be too late to be of 

 much service at the present time, but I hope to have it in readiness 

 for my next report. 



The leaves when received were found to be thickly covered with 

 honey-dew, which had already, perhaps from inclosure in the box, 

 commenced to assume the black appearance which, when further 

 advanced, is known as " black blight." This blight, as it is called, 

 is simply a later stage of the honey-dew, when, from exposure, it 

 has undergone decomposition. 



The honey-dew was thickly sprinkled with little white bits of 

 matter, which are the cast-off skins of the young lice at their 

 meltings. 



The lice upon the leaves were the young and older forms of the 

 hop-louse, Aphis humuli, known by our later authorities as 

 Phorodon. huimdi, which is identical with the European species, 

 for many years very destructive in Europe, but first noticed in this 

 country about the year 1862. Upon the leaves were also some 

 yellowish worm-like forms, of one-quarter of an inch long or less, 

 holding to the leaf by their hinder extremity, and reaching out 

 their head in difl'erent directions in search of the lice upon which 



