AND THE MBOHANIC ARTS. 527 



seen but one robin, one song sparrow and two large hawks, 

 and the writer In traveling from Bradford to Hennlker, a dis- 

 tance of ten, miles, saw only four sparrows and one black-bird. 

 But few or no birds were present In the badly infested region 

 of the Sandwich Range. 



Again, the ground mice and shrews do much toward holding 

 these Insects in check. Judging from the habits of these little 

 animals they destroy many of the pupae during the winter 

 months. Mr. Barrows reports having found large numbers of 

 empty pupae cases in their burrows. The general opinion seems 

 to be that the mice have been unusually scarce during the past 

 few years. Still, we have no absolute data on the subject. 



Weather conditions, in a general way, may nave had con- 

 siderable influence on the outbreak. If a combination of weath- 

 er conditions existed which was detrimental to the parasitic or 

 predaceous enemies of Heterocampa, but on the other hand was 

 not beneficial to the species Itself, a noted increase would nat- 

 urally result. That climatic conditions were more or less respon- 

 sible seems to be indicated by the peculiar local distribution. In 

 all cases personally observed, the most serious outbreaks have 

 been at elevations of from eight hundred' to a thousand feet. 

 Frequently a very definite line could be drawn on the mountain- 

 side, above which the trees were completely defoliated, and be- 

 low which there was no perceptible Injury. However, we can 

 only guess as to what extent this was dependent upon climatic 

 conditions. 



Many of the larvae were found diseased, but no large propor- 

 tion were thus destroyed. It is quite possible that diseases may 

 be an important factor in the natural control of the pest. If 

 so, the very unusually dry summer of 1908 would have effectually 

 checked the development of such diseases and thus permitted 

 the abnormal increase of the caterpillars. But little can be 

 predicted for the future until more is known of the habits, life 

 history, and natural enemies. The probability is that the ene- 

 mies will multiply sufficiently within a short time, to keep the 

 larvae In check, but if this does not occur the results are liable 

 to be very serious. 



Geogkaphical Distribution. 



The range of the Antlered Maple Caterpillar is in no way re- 

 stricted to New England, it having been reported' from Maine, 

 New Hampshire, Massachusetts, Rhode Island, New York, Wash- 



