December, '19] BAKER: GOOSEBERRY APHIS 433 



Table IV. Amount op Polysulpids in Lime Sulfur Treated and Untreated Combination Spray 



After 3 hra. 



After 2 days 



Lime sulfur only 



Lime sulfur and lead arsenate 



Lime sulfur and lead arsenate and lime 



4 . 360 gms. 

 1.892 •• 

 4.240 " 



4.360 gms. 

 None 

 3.040 *• 



Here again the value of adding lime to lime sulfur previous to com- 

 bining with lead hydrogen arsenate is emphasized. The polysulfid 

 content of the combination spray that had been treated with Hme had 

 decreased only a negligible amount while the untreated showed a loss 

 of almost 50 per cent of its fungicidal and insecticidal properties. 



Attention is further called to chemical changes that had continued 

 during two days: Where Hme had been previously added to the com- 

 bination spray over 75 per cent of the lime sulfur remained unchanged 

 and as efficient as ever for spraying purposes. Where no lime had been 

 added all polysulfid sulfur had been transformed into sulfid of lead or 

 to thiosulfate. In this form the spray is practically valueless as its 

 peculiar properties are destroyed. 



Conclusions 



The data herein reported indicate that there is a pronounced detri- 

 mental chemical reaction between lime sulfur and lead hydrogen 

 arsenate when mixed for a combination spray. 



The addition of lime at the rate of about ten pounds to 100 gallons 

 of lime sulfur, previous to adding the lead arsenate, prevents to a certain 

 extent this reaction. 



THE HOUGHTON GOOSEBERRY APHIS 



By A. C. Baker, Entomologist, Deciduous Fruit Insect Investigations, U. S. Bureau 



of Entomology 



In 1906 James Troop^ described under the name of Aphis hough- 

 tonensis a species of aphid injurious to gooseberries in Indianapolis. 

 Troop's specimens were taken during 1904 and later during 1905, 

 Specimens were sent to Washington and were mounted and studied by 

 Mr. Pergande. The first sending was received on July 25, 190-1. 

 On this material Pergande made the following note: "The apterous 

 females are pale dirty yellowish, the alxiomen marked with very few 

 dark or bluish-green, scattered spots; the eyes dark brown; the anten- 

 na; j'ellowish with apex of the 5th, the Gth and the spur dusky; nec- 



' Ent. News Phila., Vol. 17, p. .'i9-G0. 

 3 



