10 



BULLETIN 204, U. S. DEPARTMENT OF AGRICULTURE. 



Compsilura is present in more localities in Maine, but we have been 

 unable to secure definite records to that effect. The following table 

 is interesting, as it shows the general rate of dispersion of this para- 

 site. The spread recorded is based on distance from Melrose High- 

 lands, Mass., and is mostly due to natural spread, although a few 

 small colonies have been liberated outside of the area where the 

 species was known to occur in 191 3-. 



Table I. — Dispersion of Compsilura concinnata. 



Highlands, Mass. 



Distance recovered from Melrose 





1913 



1914 



From Melrose Highlands: 

 North 



Miles. 

 75 

 100 

 50 

 40 

 50 

 70 



Miles. 

 100 

 130 

 50 

 55 

 65 

 80 





South 



West 







It is undoubtedly true that this species is now present over an 

 area which would be represented by connecting the points indicated 

 by the directions and distances given in the table for 1914. (PI. VI.) 

 Four thousand five hundred and sixty-five Compsilura were liber- 

 ated in 10 new towns in 1913 and 10,000 were placed in 21 new 

 towns in 1914, as follows: Eight in New Hampshire, 5 in Vermont, 

 2 in Massachusetts, 2 in Rhode Island, 3 in Connecticut, and 1 colony 

 was forwarded to a substation of the Bureau of Entomology at 

 Koehler, N. Mex., in order to test the value of this species as an 

 enemy of the range caterpillar (Hemileuca oliviae Ckll.), an insect 

 which is causing enormous damage to the grazing lands in that State. 

 In addition to the number of specimens of this species colonized in 

 1914, about 5,000 were secured by Mr. McLaine and shipped to New 

 Brunswick; about 3,000 were secured by Mr. R. S. Ferguson, assist- 

 ant in the moth department of the State of Maine, who, with several 

 assistants, were collecting for the purpose of establishing colonies in 

 that State, and over 2,500 were collected and colonized by Prof. 

 O'Kane's assistants in New Hampshire. 



Three hundred and sixty-five sample collections of gipsy-moth 

 larvse which were secured during the summer of 1914 from scattered 

 localities in Maine, New Hampshire, Massachusetts, and Rhode 

 Inland, consisted of over 99,000 caterpillars. This material required 

 the use of over 500 rearing trays at the laboratory and the constant 

 attention of several assistants to feed the larvae in each tray and 

 record the parasitism, mortality, and other data. 



Based on 25 collections of gipsy-moth larvae taken at widely scat- 

 tered points in the gipsy-moth-infested area and aggregating 46,000 



