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Lachnosterna show that the common species of this genus pupate and 

 emerge in the hitter half of the growing season, as adults in the earth. 



The genus Cyclocephala, on the other hand, has the other habit, if we 

 may judge from our own observations on C. immaculata, made in 1887, 

 1888, and 1890. 



For example, grubs of this species collected in grass lands at Urbana, 

 April, 1887, had all emerged as adults July 19 ; others collected from 

 cornfields April 25, 1888, had pupated, at least in part, June 20, and 

 afterwards gave the imago — at what date is not known. 



In April, 1890, grubs were collected from the 6th to the 29th, all of 

 which but one had pupated by June 4, and all had emerged July 19. 



A dozen of the itnagos of this collection being placed in a breeding- 

 cage and furnished regularly with fresh sods, had laid pumerous eggs 

 among the grass roots July 2, and fiv^e days later one of these had 

 hatched. July 20 several young larvae were living and doing well, but 

 by August 10 all had died. 



Distinguishing larval characters, at least of genera and subdivisions 

 of genera, are to be found in the last segment of the abdomen. Cyclo- 

 cephala may be told at a glance from Lachnosterna by the fact that its 

 supra-anal plate is very much larger and that its vent is a transverse slit, 

 while in Lachnosterna this opens beneath a triangular flap, making a 

 large V-shaped slit. Larv?e of the latter genus may be subdivided to a 

 considerable extent, although not always as to species, by differences in 

 the hairy clothing of the under surface of the last segment, in front of 

 the vent. There is here a median longitudinal avenue of short blunt 

 spines (lacking in Gyclocephala), which differ constantly in respect to 

 the size of the spines, their number and distance in a row, their direc- 

 tion, and the distance of the rows from each other. 



There are also difterences here in the extent and density of the coat 

 of bristle-like hairs, many of them hooked at tip, which largely clothe 

 the surface on each side of these median rows. By these means my 

 assistant, Mr. Hart, whose duty it has been to assort the white grubs 

 collected into provisional species for the breeding cages, has clearly 

 discriminated five groups, the differences in which appear constant at 

 all ages. One of these groups was subsequently bred to both hirticula 

 and rugosa, one to inversa and one to gibbosa, but the other two we have 

 not yet brought to the adult. The form from which we have obtained 

 inversa almost certainly represents fusca also, as it is much the com- 

 monest grub, and this is the commonest imago with us; but, curiously, 

 fusca has not yet appeared in our breeding cages. 



Mr. Smith said that he had made the same observations relative to 

 the transformations of the white grubs in fall some years since and 

 published it in his Lachnosterna paper in the proceedings of the U. S. 

 National Museum. It was also announced at the time at a meeting of 

 the Entomological Society of Washington. 



