16 



THE AMEEICAN ENTOMOLOGIST. 



comes out of the ground soon after the leaves 



of the currant and gooseberrj- bushes, upon 



wliich it feeds, put forth in the spring, or from 



[Pig- v.] 



Colors — Bliick and yellow. 



the latter part of April to the forepart of May. 

 The sexes then couple, and tlie female proceeds 

 to lay her eggs along the principal veins on the 

 under side of the leaf. From these eggs shortly 

 afterwards hatch out minute green 20-lcggcd 

 larvae or worms, which at first have black heads 

 and many black dots on their bodies, but after 

 moulting for the last time arc entirely of a grass- 

 green color, except the large dai'k eye spots on 

 each side of the head found in all larvffi belong- 

 ing to this genus, and except that the joint next 

 the head and the two hindmost joints are of a yel- 

 low color, as is also the case in the less mature 

 larva, which bears so many black markings. In 

 the annexed Figure 8, a, a, a, a shows larvse of 

 different sizes in different positions : and b gives 



ms- 8.] 



Colors— Gi'een, yellow .and black. 



an enlarged view of one of the abdominal joints 

 in profile, so as to exhibit the position of the 



black spots. When full-grown the larvas arc 

 about three-quarters of an inch long, and from 

 their greatly increased size, make their presence 

 rcadilj' known by the sudden disappearance of 

 the leaves from the infested bushes. Shortly 

 afterwards, having attained a length of fully 

 three-quarters of an iuch, they burrow under- 

 ground, generally beneath the infested bushes, 

 or, if there are many leaves h'ing on the ground, 

 simply hide under those leaves. In either case 

 they spin around themselves a thin oval cocoon 

 of brown silk, within which they assume the 

 pupastate. But frequently, as we are assured by 

 Mr. Saunders of Canada West, and as European 

 observers have noticed, they spin their cocoons 

 in the open air upon the bushes. About the 

 last week in June or the first part of July, or 

 occasionally not until the beginning of August, 

 the winged insect bursts forth from the cocoon 

 and eniergos to the light of day ; when the same 

 process of coupling and laying eggs is repeated. 

 The larvas hatch out from this second laying of 

 eggs as before , feed on the leaves as before, and 

 .spin their cocoons as before ; but the perfect fly 

 from this second brood does not come out of the 

 cocoon till the following spring, when the same 

 old series of phenomena is repeated. 



From the drawings of the Male and Female 

 Fly given above (Fig. 7), the reader will sec 

 at once that the two sexes differ very widely. 

 This is very generally the case among the Saw- 

 flics, and it is a remarkable and most suggestive 

 fact that, when this takes place, the body of the 

 male is almost invariably darker than that of 

 the female. Nor does our species, as will be 

 observed at the first glance, form any exception 

 to the rule. Indeed, as with two other Sawflies 

 that devour the foliage of our Pines and Firs 

 {Lopliyrns Abhottii and L. abietis), the body of 

 the male is almost entirely black and that of the 

 female almost entirely yellow ; so that at first 

 sight we should suppose the two to belong to 

 different species. Since, from some unaccount- 

 able oversight, Dr. Fitch has overlooked this 

 fact, and described both sexes as being colored 

 in the manner which is exclusively to be met 

 ■with in the female, it will be as well to add here 

 full descriptions, first of the female fly and 

 secondly of the male fly. These descriptions 

 were, indeed, published by the Senior Editor 

 two years before Dr. Fitch's appeared ; but the 

 writings of that gentleman circulate so exten- 

 sively that, when he makes an important mistake 

 such as this, it is proper that it should be cor- 

 rected in our columns in detail. 



Female Fly. — General color of body bright hoiioy- 

 ycUow. J/ead black, with all the parts lietwecn aiiil 

 below the origin of the .antcnn.'c, except the tip of the 



