20 



All of the remaining insects were brought to the laboratory 

 from four different points in the field. In all 52 insects were 

 thus brought in, and in addition tests were made of two spiders. 

 Five orders of insects were represented (Table II), and posi- 

 tive results were obtained from insects in all of these except 

 the Lepidoptera, of which only two members were tested. Of 

 the 52 insects from the field 19 were found to be carrying 

 spores of the blight fungus, but both of the spiders yielded 

 negative results. The number of viable spores of Endothia 

 parasitica per insect ranged from 74 to 336,960, and five yielded 

 over 4,000 spores each. An abstract of these results has already 

 been published (51). 



Reference has been made in the introduction to Leptostylus 

 macula, one of the beetles which feeds on pustules of the blight 

 fungus (Figs. 1 and 2). Only eight of these beetles were 

 tested, but all of them yielded positive results. It will be 

 noted that of all the insects tested, the three which yielded 

 the highest numbers of spores of the blight fungus belonged to 

 this species of beetle. A photograph was made of the plate 

 cultures from one of these, insect No. 30^ after 6 days of 

 growth, and this is represented in Fig. 3. 



On the strength of these results we cannot agree with the 

 conclusions drawn by Craighead (9) and by Anderson and 

 Babcock (2), for the large numbers of spores carried by this 

 beetle certainly indicate that it may be an important agent 

 in the dissemination of the blight fungus. 



It has been shown by Anderson and Babcock (see p. 14) that 

 spores will stick to the bodies of ants during their normal 

 movements in a bottle of earth for at least five hours. In our 

 tests most of the insects were brought in from the field in glass 

 tubes. Those from West Chester and Valley Forge were kept in 

 these tubes for at least two hours before they were transferred 

 to flasks of water^ and those from Lehighton for a much longer 

 time. The fact that positive results were obtained from many 

 of these bears out the results of the above mentioned writers. 



In this connection, however, it might be asked whether the 

 spores might not stick to the feet and body of the insects to 

 such an extent that they would not be brushed off during any 



