18 



THE AMERICAN ENTOMOLOGIST. 



pleuly of food without wandering: oft", and they 

 have the habit when very young of boring small 

 holes through the leaf as shown at IS'o. 2 in Fig- 

 ure 0, and when they become a little older, 

 holes that are a little larger as shown at No. 3. 

 It is evident that such holes as these may be 

 readily recognized, and the leaf be carried larvae 

 and all far away from any currant or gooseberry 

 bushes and left to wither there, or— to make 

 assurance doubly sure — thrown into the fire. 

 If, however, the young larvas are removed a few 

 rods away from any plant belonging to the 

 botanical genus Eibes ( Currant and Goose- 

 berry), they will be sure to die of starvation. 

 For they cannot feed on anything else, any more 

 than the common Locust-borer can live on an 

 Apple-tree. As the eggs are laid in such large 

 groups, there will be but a few leaves bearing 

 these newly hatched larvje to remove from every 

 bush. 



Wherever this Currant Worm has been in- 

 troduced, there has prevailed from some cause 

 or other a popular superstition, that the currants 

 grown upon the infested bushes are poisonous. 

 This is a mere delusion. They may be, and 

 very probably are, unwholesome, just as any 

 other fruit would be perhaps more or less 

 unwholesome, if grown under such unnatural 

 conditions as to seriously aflect the health of 

 the tree; but we have the authority of Dr. 

 Fitch, himself a physician, for believing that 

 the common notion on this subject is entirely 

 erroneous. 



Entomologists have often speculated, whether 

 the same parasite will attack several distinct 

 species of insects, and whether any European 

 species, which has been introduced into America 

 without its peculiar parasites, will ever be 

 attacked by the indigenous parasites of this 

 country. So far as regards our Imported Cur- 

 rant Worm, both these questions can be an- 



swered in the aifirmative. Three years ago the 

 Senior Editor published the fact, that this worm 

 was parasitically infested by the larva of a small 

 Ichneumon-fly ( Brachyjiterus micropterus, 

 Say), which has such short and rudimentary 

 wings, that it has very much the appearance 

 of an Ant; and more recently it has been dis- 

 covered by that excellent observer, J. A. Lintner 

 of Schoharie, N. Y., that the eggs of this Currant 

 AVorm Fly are so generally inhabited by the 

 larva of a minute Hymenopterous Parasite, 

 that among fifty eggs he only found four or five 

 which hatched out into Currant Worms. 



As these pages were going through the press, 

 we received trom the Editor of the Canadian 

 Entomologist a third parasite, which he had 

 himself ascertained to prey, not on the egg of 

 the imported Currant Worm Fly, but on the 

 larva. This parasite is a small four-winged fly 

 belonging to the great Ichneumon Family, and 

 scarcely one-fifth of an inch long, with its front 

 wings very prettily ornamented each of them 

 with two dusky bands. A full description of it 

 (under the name ofJlemitelesnemativorus, n . sp.) 

 will probably appear before long, from the pen 

 of the Senior Editor, in the columns of the ex- 

 cellent Periodical just now referred to. This 

 very same species of Ichneumon-fly had been 

 captured near Rock Island, 111., several years 

 ago by the Senior Editor; and as the Imported 

 Currant Worm has not as yet been introduced 

 into that region, we must conclude that this 

 Ichneumon-fly could not have been imported 

 into America from Europe along with this Cur- 

 rant AVorm, but that in all probability it is an 

 indigenous species. Hence Ave have additional 

 proof that, uuder certain circumstances, native 

 American parasites can, and actually do, ac- 

 quire the habit of preying upon Eui'opean in- 

 sects when the latter are imported into America. 

 It is certain, however, that they will not do so 

 in all cases without exception ; for although the 

 AA''lieat Midge, or Red AA^eevil as it is incorrectly 

 termed in the AVest, invaded our shores some 

 forty or fifty years ago, not a single parasite has 

 yet been discovered to prey upon it in this 

 country, although there are no less than three 

 that prey upon it in Europe. 



The Sawfly Family {Tenthredo), to which 

 both this and the next species to be noticed 

 belong, derives its name from the "ovipositor" 

 or egg-laying instrument being modified so as 

 to inimick the blade of a saw. Under the mi- 

 croscope — and in the larger species even under 

 a good lens— it will be seen that the lower edge 

 of each of the two horny blades, of which this 

 iustrumcut is composed, is furnished with very 



