282 MAINE AGRICULTURAL EXPERIMENT STATION. 



ance on the spruce in Maine, where it produces swellings at 

 the ends of the twigs resembling in size and form the cones 

 of the same tree." Dissection of the galls, of course, proved 

 they were not abnormal cones but abnormal shoots. 



The mistaken identity of the so-called "cones" seemed a 

 good joke entomologically and as the collector of the galls 

 is a plant morphologist perhaps not less so botanically. 



Both the galls and the Chermes in them are distinct from 

 abietis and there seems no ground for doubting that this species 

 is abieticolens. 



Some of the more advanced galls of Chermes abieticolens were 

 opening on date of collection, June 14, and by June 21 fresh 

 Chermes pinifoliae were on the needles of White Pine every- 

 where in the neighborhood of Orono. Others were sent in 

 from other parts of the state a little later. Accompanying 

 such specimens from Gilead vicinity on June 25 "millions of 

 the flies on white pines" were reported. 



As the disappearance of the emerging abieticolens from the 

 spruce coincided exactly in time with the appearance of pini- 

 foliae on the white pine and as there was no apparent difference 

 in the Chermes in these two situations the conclusion was obvious 

 enough and careful microscopic comparison was, of course, made. 

 There was no difference between the two discoverable in any 

 structure submitted to this sort of examination. The freshest 

 of the specimens on the white pine had of course to be used for 

 the comparison. 



A check migration test was made June 22. A lot of galls 

 from the black spruce were placed in a cage with fresh twigs 

 of various conifers. On June 25, more than 200 individuals 

 had settled on the white pine where they remained with their 

 eggs. Although specimens were found crawling over some of 

 the spruce twigs supplied them no individual settled and ovi- 

 posited except on the white pine. This was more overwhelm- 

 ing preference than is usual with a cage test, for often in con- 

 finement a few stray specimens oviposite amiss, as it happens 

 also to insects in the open. Perhaps if the test had been pro- 

 longed some of these would, but three days with the uniform 

 result of 200 to o seemed sufficient. 



In confinement, as in the open, these Chermes settled on the 

 pine needles with the head toward the base of the needle. Out 



