For more than twenty years I have been endeavoring to complete the synonymy of our moths, and to find out what species were covered by Walker's and Gueneé's descriptions. During this time I have made three trips to Europe, with this object more or less directly in view. Comparatively few of M. Gueneé's species remain unknown to me; and as many of these were collected by Doubleday, the types will probably be found in the British Museum. Mr. Gueneé's descriptions of species are good, and among the best extant, but he does not give structural characters. The microscope lvas not used by him. His genera contained incongruous material. When he had a species that he did not know what to do with, instead of making a new genus for it, which would have assisted the identification of the species, he often made a group of it, under a genus to which it was opposed in every structural feature—and the species in this way was readily over-looked. As, for instance, Leucania Littera.

After a comparison of my types with Mr. Walker's, Mr. A. G. Butler writes me that Walshii Edw., as taken by Prof. Snow in Kansas, is the same as Functura of Walker. The form which has been taken about Albany and which is exactly like Unijuga, but differs by the band being a little narrower on hind wings and not quite so continuous, is an unnamed variety of Unijuga. It follows from this that my Arizonœ is certainly not Walshii, as suggested by certain parties. Mr. Neumoegen has received it in quantity from Arizona. The form taken by Belfrage in Texas, and distributed as Walshii, may be the same as Arizonœ, and should be carefully compared with Arizonian specimens.

In the January number of the Canadian Entomologist I described two new species of this interesting family under the names of Isosoma Allynii and I. Elymi. Professor C. V. Riley, to whom a pair of the first were sent, writes me that they belong to the genus Eupelmus instead of Isosoma. From a re-examination of my specimens I think he is correct, and the species will be known as Eupelmus Allynii, instead of as first described. They have 11 joints to the antennæ, and the prothorax short.

Since writing the descriptions above referred to I have had a number of wingless insects hatch from my wheat straws, and it is now evident that the description of chrysalids, and perhaps larvæ, as given under Isosoma Allynii, can not apply to that species, but to these wingless specimens. In a recent letter Professor Riley states that he has bred wingless specimens of an Isosoma from wheat received from Kentucky, and it is probable these are the same. I am inclined to think they belong to Isosoma Elymi that I obtained from the stalk of Elymus Canadenis, though it will be difficult to say positively without more specimens of Elymi or winged specimens of the other.

8. On Young Caterpillars Eating their Egg Shells.

Mr. Scudder, Butterflies, p. 101, says, after describing the way in which the caterpillar eats out of the egg: “The taste he has gained of egg-shell seems to allure him; for, strange as it may seem, although placed by the provident parent within immediate reach of choice and succulent food, he will not taste it until he has devoured the last remmant of his prison-walls. Strange food this for a new born babe! The act, however, is plainly a provision of nature by which the tender animal is rid of a sure token to his enemies of his immediate proximity.” Surely here is an error in fact, and a wrong conclusion whatever the fact may be. I read the above statement on the 25th July last, and at once went to my garden to search for eggs of Libythea Bachmanni, on Hackberry leaves. The young caterpillars of this species are green, of a shade so near that of the leaves they feed on, that it is very difficult to discover them. Even where the tip of the leaf has been eaten, and their presence is suspected, it is easy to overlook them. I found at once three eggs and one young caterpillar. The egg from which this caterpillar had come was present at the base of the leaf on the extreme tip of which the little creature rested. A hole was in its side near the top, and no more had been eaten than just enough to permit egress.

On the evening of August 13th, 1881, I observed them between the hours of 5 and 7 o'clock. The air for miles around seemed literally alive with these dragon-flies, from a foot above ground to as far as the eye could reach, all flying in the same direction, a south-westerly course, and the few that would occasionally cross the track of the majority could all the more easily be noticed from the very regular and swift course they generally pursued; but even these few stray ones would soon fall in with the rest again. Very few were seen alighting, and all carefully avoided any movable obstacles.

The next day very few were seen on the prairies, and these mostly of another species very abundant in this country, Anax junius (Drury), which were probably at home previously, and in a few days I could see none others but the latter. A few newspapers, and also a few correspondents from twelve to fifteen miles east and west of here, had observed and mentioned their flight.

No one I think can have been long engaged in collecting insects without having noticed the remarkable diversity in the products of different years, not only in quantity, but in kinds. Each summer seems to bring its own particular species to the front, so that if a person wishes to get a moderately correct idea of the insects of any locality, it is necessary for him not only fo hunt diligently all the season, but every season for a considerable length of time; and if he has from any cause missed one, he may be sure he has missed something which it may be years before he will again have an opportunity of securing, or securing in the same abundance. The causes of these variations seem as yet to a great extent a mystery.