16 



Other parasites of this scale are Aphycus pulvinarice How., described 

 from specimens reared by Mr. Putnam in Iowa, and Comysfusca How., 

 a common and widespread parasite of Lecaniine scales. 



Remedies. — In view of the statement already made that the insect is 

 rarely injurious in two consecutive years, it might seem as though no 

 remedies were really necessary ; but it has been found, in the experi- 

 ence of the city of Brooklyn, that the damage in a single season may 

 be so great as to render long rows of shade trees unsightly. It is con- 

 sidered, therefore, to be the best policy, when the insect appears in great 

 numbers, to await thehatching of the young and shortly thereafter to 

 prune rather severely. In the case of especially valuable trees this 

 pruning should be followed with either a summer spraying with a dilute 

 kerosene soap emulsion or a winter spraying in the autumn with whale- 

 oil soap in the proportion of 1 pound to 2 gallons of water. It is not 

 difficult to determine whether the winter spraying is necessary by a 

 careful examination of specimen twigs from trees in different parts of 

 the city. Thus, in the winter of 1888-89, it was easy to see in Wash- 

 ington that the scale would be scarce the following summer, while in 

 Brooklyn Mr. Collins was able to determine the exact localities in the 

 city where insecticides would probably be necessary the following season 

 by estimating the proportion of living scales. 



II. THE MAPLE LEAF PULVINARIA. 



(Pulvinaria acericola W. & E.) 



Original home and present distribution. — This scale insect is also 

 apparently a native of the United States, and seems to have been also 

 originally found by the late Dr. S. S. Eathvon at Lancaster, Pa. He, 

 however, while calling attention to the fact that there are probably two 

 species of Pulvinaria to be found upon the maple tree, one of them 

 occasionally being found upon the leaves, did not decide to establish 

 any specific distinction between them. 



In Volume I of the American Entomologist, however, Riley and Walsh, 

 on page 14, figured a Pulvinaria upon a maple leaf received from B. W. 

 McLean, of Indiana, to which they gave the name Lecanium acericola. 

 This was considered by later writers, namely, J. Duncan Putnam and 

 Emily A. Smith, to be synonymous with the Pulvinaria innumetabilis 

 of Eathvon, and it was not until the writer in Bulletin No. 17, new 

 series, of this Division, pages 57-58, called attention to the excellence 

 of this figure and to the distinction between the insect represented and 



that lie reared from it several brilliant green parasites. Examining the type speci- 

 mens of Fitch's Lecanium ribis, now in the possession of the United States Department 

 of Agriculture, Mr. Pergande found that the scales had disappeared, but that the 

 small bunch of Eunotus cocoons was attached to the twig in such a position that 

 they were under the original scale. The minute perforations in these cocoons 

 showed that the parasite mentioned by Fitch was a secondary parasite, probably of 

 the genus Tetrastichus. 



