[49] Report of the State Entomologist. 145 



journals, but perhaps in consideration of its efficacy, it can not be too 

 often repeated. Briefly stated, in a simple sentence, it is this: The 

 emulsion is produced by violently agitating through the nozzle of a 

 force-pump until emulsified in a homogeneous mass, two gallons of 

 kerosene combined with one gallon of a hot soap solution, made by 

 dissolving a half-pound of common soap in a gallon of water. The 

 ordinary dilution of the emulsion for general use is one part of the 

 emulsion to nine parts of water. 



As quite an amount of labor attends the production of the emulsion, 

 it would seem to be desirable that the " kerosene butter," as it has 

 been called, should be manufactured in quantity and placed in the 

 market for sale as are a number of other insecticides of far less 

 merit. Its cost of production is so slight that the price at which it 

 could be offered and command, we believe, a ready and extensive 

 sale, could not fail of yielding a large profit to the enterprising 

 manufacturer who would undertake to bring it properly before the 

 agricultural community. 



As a Grapevine Pest. 

 As previously stated, this insect frequently occurs on grapevines. 

 It was received by me from a gentleman in Essex county, Mass., 

 with the following note : 



I send you to-day a piece of grapevine cane with several cocoons, 

 as they appear to be, upon it ; and a few grape leaves with a different 

 but similar cocoon on them. The vines are under glass, but the 

 specimens were taken from different houses. I have never seen such 

 before and do not know whether they belong to a friendly or 

 injurious insect. Will you please give me some information regarding 

 them. 



As the reply made contained some items not given in the above 

 notice, portions of it are herewith presented. 



The pieces of vine and accompanying leaves are infested by a per- 

 nicious enemy of the grape — the Pulvinaria innumerabilis (Rath von). 

 It is one of the obnoxious family of Coccidce (subfamily of Lecanince), 

 nearly all of which possess remarkable powers of multiplication, and 

 eventually, if left to themselves, increasing until they nearly or quite 

 cover the surface of the plant or tree on which they occur. When 

 they have become so numerous as this they cause the death of the 

 plant, as their nourishment is drawn from the juices by means of a 

 proboscis inserted through the bark. 



In the examples received, the milk-white cofcton-like mass that pro- 

 truded from one end and the sides of the brown suboval scale, 

 19 



