198 The Ohio Journal of Science [Vol. XVIII, No. 6, 



out the entire period of adult life, probably a month in nature. 

 Basing the above number of eggs per day on this period of 

 oviposition, the maximum number of eggs that can be laid is 

 one hundred and eighty. 



Egg. — Since the egg is very minute and often is thrust down 

 deeply into the body, it is practically impossible to locate it 

 either by dissection or by sectioning the host. For this reason, 

 the date of hatching is still in doubt, and the incubation period 

 can only be estim_ated from the time the egg is laid to the 

 appearance of the sac outside the body-wall of the hopper. 

 In Gonatopus erythrodes (Perk.) a blackish discoloration precedes 

 the appearance of the sac by several days, and is noticed five 

 days after oviposition. Since in this case the discoloration 

 is due to the black sac beneath the cuticle, the egg must have 

 hatched within two or three days after being laid. 



Larva. — The earliest stages of the dryinid larva have been 

 described by Keilin and Thompson (1915) for Aphelopus 

 malaleucus Dalman parasitic on Erythroneura (Typhlocyba) 

 hippocastani. They report finding an embryonic stage within 

 the tissues of the host, and do not consider it as the first 

 larval stage. The exact relation of this "embryo" to 

 the first stage larva is not known. It is possible that 

 this may be the true first instar, which may be modi- 

 fied and different from the following ones. In case the 

 egg is internal, just previous to emerging from the host, the 

 larva is seen to be curved into the form of a U, the apex of which 

 appears first between the segments. This is the second larval 

 stage, and it is covered almost entirely and protected by the 

 exuvium of the first instar. The appearance of the sac exter- 

 nally on the host takes place in from five to seven days after 

 oviposition. During this time the egg has hatched, the 

 "embryonic" stage has been passed, and a molt has taken 

 place. 



The second molt occurs in from five to ten days after the 

 emergence of the sac, and is indicated by the rupturing of the 

 first exuvium along a median dorsal line. Between the gaping 

 halves of this split, the second exuvium is gradually pushed 

 outward by the growth of the larva within, now in its third 

 instar. Accompanying this split there is often a change in the 

 coloration of the sac, as from dark green to black. 



