April, '16] DAVIS: WHITE GRUB IXVESTIGATIOXS 265 



former pupating in spring and appearing about the same time the 

 Cyclocephalas are out, and the Euphorias maturing in fall and appear- 

 ing above ground quite early in spring. The grubs of these two genera 

 are interesting because they crawl on their backs and their normal food 

 is decaying matter, particularly animal manures. The habits of the 

 beetles likewise differ from those already discussed in that they fly 

 during the day. All of the Anomalas which we have studied have a 

 one-year life cycle, maturing in the fall and appearing above ground 

 the following spring. Our observations indicate that the grubs feed 

 on living rootlets but apparently they are never sufficiently abundant 

 to noticeably damage crops although they may at any time prove 

 important crop pests. In the beetle stage certain species feed on 

 tender foliage and flowers at night while others are active during the 

 day. The grubs of Cotalpa lanigera rank close to those of Lachnosterna 

 in economic importance in some sections. In the "thumb district" 

 of Michigan and along the lake in the vicinity of Holland, Michigan, 

 these grubs are destructive to raspberry bushes, strawberries, corn, 

 grass, etc. We have not yet completed our life-history studies of this 

 species but the grubs in our cages started in 1914 were very small when 

 examined this fall (1915) and it will take four years and possibly five 

 years to complete the life cycle. Polyphylla grubs are more nearly 

 like Cotalpa grubs in their habits and life-history. Grubs which 

 proved to be those of P. variolosa were shown us by Dr. T. J. Headlee 

 who reported them as destructive to crops in southern New Jersey 

 and a supply of the grubs received from the farmer reporting the 

 trouble showed many sizes, indicating a four- or five-year cycle for 

 this species. Phytalis and Listochelus, species of which genera belong 

 to the southern fauna, have similar habits and resemble the Lach- 

 nosterna grub but have not yet been studied enough by us to make 

 generalizations. 



So many have written for information to distinguish the different 

 white grubs that it seems pertinent at this point to mention some of 

 the more conspicuous characters to distinguish the grubs of Lach- 

 nosterna from those of related genera. 



The Lachnosterna grub is white or cream white, the dark contents 

 of the intestinal tract being plainly visible through the skin of the last 

 few abdominal segments. The head is light tan in color, smooth and 

 shiny and the body is covered with reddish brown hairs, those on the 

 dorsum of the folds or ridges being short and more thickly placed. 

 The ventral surface of the anal segment, which shows the most promi- 

 nent character, bears a triangular patch of brownish hairs which are 

 hooked at the tip, with an intermixing, especially at the borders of the 

 patch, of fine, long hairs, and with a median longitudinal double row 



