the vine in cultivation. One thing seems very certain, that in order to render the sulpho-carbonates practically efficacious in killing the insect, it is necessary to use water as the vehicle by which they may be brought to all the underground parts of the plant, and that the best time of the year for their application is the winter or early spring, when the earth is still moist and the quantity of water necessary to be brought on to the ground by artificial means is consequently less. Mixed with lime in the proportion of two to one, these sulphocarbonates give a powder which can be spread over the ground before the heavy rains, that is, between October and March, and which will probably prove itself very efficacious.

The conclusion at which M. Mouillefert arrives at the end of his report is that the efficacy of the sulpho-carbonates is proved, and all that is necessary is to bring to perfection their employment in agricul ture, whieh can only be accoinplished by the intelligence and practical knowledge of the vine grower who is well able to discover the economic processes of culture which are conducive to their successful application.

He ends by saying that "Science has accomplished its mission, and it remains for Agriculture to fulfil its part" in the eradication of the Phylloxera from the vineyards of France.-Nature.

FIELD RECORD.

Hints on Hunting Catocala.-My experience in this localityN. W. Philadelphia-has been that Catocala serena, Edwards, C. obscura, Strecker, C. flebilis. Grote, C. reteta Grote, secrete themselves far better than any in the group except C. antinympha, and I do not doubt that the cause of these being marked rare in some localities is simply that they are not hunted for properly. When hunting for these I always arm myself with a stout switch or young sapling and then look for trees with very loose bark. After giving the tree an outward inspection and taking off anything I may see, I give it a beating, not a few light taps, but a good thrashing commencing at the bottom and working up and around; nearly always I start some of the above from under the bark. The shellbark Hickory tree, (Carya alba) is an exellent example, and on this tree I take C. serena, and on no other unless it has been disturbed, generally it will alight on the same

tree, but a little above the place from which it came out. As an instance of how difficult they are to be disturbed, I have whipped a tree as I supposed thoroughly, and upon leaving would give it two or three heavy blows as a parting salute, when to my surprise out would fly one or more of the above species; on several occasions I have had them drop at the base of the tree crushed.-J. S. J.

Good Words.-Mr. James H. Bell, in a communication to the Canadian Entomologist, says: "I think it would be beneficial if a portion of the journal-space were devoted each month to a notice of the localities, habitats, food and habits of some of our rarer species, the best methods and apparatus for their capture, and the most approved way of putting them to death without damage, as also of pinning, setting and preserving them. These matters may seem of but slight consequence to the practiced collector, but they assume an aspect of the greatest importance in the eyes of a beginner. In this connection, if entomologists would relate their experience in successfully collecting certain families of insects and describe any method, implement or apparatus which they have found advantageous, and at the same time record the date, time of day, locality and habitat of their captures, a judicious selection of the same would, I think, add much to the popularity, and not a little to the utility of the journal."

[As this expresses our ideas upon the subject, we gladly give it space, and invite the readers of Field and Forest in all branches of natural history to make use of our pages for the recording of any interesting notes of original research, observation, or experiment, as above, that may be gleaned in the various fields of study occupying their attention. Knowledge is the accumulation of little facts, and little facts or discoveries often lead to more important ones. Our "Field Record was established for this purpose, and we only wish our many readers, who are also workers, would make use of it.—ED.]

Note on the Green Snake.-We have always understood that this quite common little snake would not feed in confinement, and such has been our experience heretofore, as well as the experience of a number of readers of this journal whose opinions we had asked. Last fall a fine specimen was brought to us alive, and was kept in a wardean case all Winter, refusing any food that was offered. With the advent of Spring, however, our attempts to feed the little creature were

rewarded with success, a repast of croton bugs, cockroackes, with large flesh flies for dessert, having temped his snakeship to break his long fast and show the manner in which he catches and devours his prey. Since then we have seen him feed a number of times.-C. R. D.

Two Pupa in One Cocoon.-I found in opening some cecropia cocoons lately, two pupæ in one cocoon. These were of different sex, and in opposite position as regarded the loose end of cocoon; neither was perfectly formed, apparently owing to their being crowded out of shape in the limited space. The cocoon was one of the "loose" kind; both inner and outer cocoons and floss were uniform in texture, showing no line by which the work of two larvæ could be distinguished. There was, however, a rudimentary division on the inside of the inner cocoon at its close end, partly enclosing the abdominal end of the pupa.-C. E. WORTHINGTON, in Canad. Entom.

CORRESPONDENCE.

The following letter received through the Smithsonian Institution, we take pleasure in presenting to our readers entire: "A year or two ago I read some articles in The Popular Science Monthly upon 'singing mice' and the question was mooted, whether they sang when in their normal state of health. I had heard them sing, but had no experience as to what their condition was until the past six weeks. I now feel sure that it is not health that inspires their song, but rather a realization of the dying Swan.

This winter our whole place became infested with the common house-mouse (Mus musculus,) and after finding traps and springs of no avail to abate the nuisance we at last resorted to poison, using phosphorus paste for that purpose. For three or four days we considered even that a failure, as mousie seemed as active and ubiquitous as ever; but about the fourth or fifth night every wall in the house, up stairs and down, bed rooms, sitting rooms, dining room, library, parlor and halls were vocal with the sweetest twitterings. They commenced about eleven o'clock, and woke me from a sound sleep. I had a few days before received some new fish for an aquarium that sits in a room adjoining my bed room, and I thought I had fallen upon the wonder, a musical fish. But on rising and softly approaching the

aquarium, I found it was not there, and soon after detected the sound in the wall. By the time I returned to my own room I found there were serenaders there also; they continued to multiply until, as I have stated above, there was not a spot on the premises where their voice was not heard. Finally they sang all day, leaving their lurking places within the walls, and boldly—or stupidly-coming out on pantry, china closet, and library shelves and even upon the floor, singing away regardless of observation. Every morning the maid would. find them on the carpet dead; sometimes one or two in each room, sometimes more, until finally the songs died out and the mice too. We have not seen a mouse nor heard so much as a nibble for three or four weeks, they seem to be entirely exterminated.

The volume and tone of their song seemed almost identical with that of a young canary, when first learning to sing, though now and then rising to fuller and more varied power.

Thinking, perhaps, these facts might be interesting to you I have presumed to send them."

Houston, March 30.

MRS. M. J. YOUNG.

Dear Sir:

The article in the April number of Field and Forest p. 173, headed "Hints upon Skeleton making," by M. E. B., reminds me of an experiment I saw printed some twenty years ago and which I tried; I herewith send it, as near as I can recollect. I think it was entitled, "To make skeletons of small fish or other small objects." It was suggested to take the object to be made a skeleton of, to a pond where there are plenty of tadpoles, suspend it with waxed thread in their midst, and, when the flesh commences to decompose, the tadpoles will thouroughly cleanse the skeleton of every particle of flesh and fibre. It can be then taken out by the threads, and be bleached.

I tried it with a small fish, suspending it by means of threads under the gills and tail to two sticks. In the course of four weeks, I had a beautiful skeleton hanging in the loops. Not being a student of osteology, however, I did not carry the experiment any farther, neither can I say whether the tadpoles ate the flesh, or wether it was cleansed by their swimming through the frame.

Frankford, April 16, 1877.

J. S. JOHNSON.

Field and Forest

A MONTHLY JOURNAL

DEVOTED TO THE NATURAL SCIENCES.

VOL. II.-JUNE, 1877.-No. 12.

Insects in Colorado.

About a year ago we gave in this journal a short article on the "Comparative Scarcity of Insects in the Mountains of Colorado." Mr. Meehan, in the January number of Popular Science Monthly, writing on the fertilization of flowers by insect agency, quotes a portion of our remarks as bearing him out in a previous statement to that effect, which had been questioned. To a request from him for a list of insects found in the Rocky Mountains, a letter in reply, written by Mr. J. Duncan Putnam, is published in the March number of the same journal, which would go to prove that insects are not scarce in the locality in question.

It is not our purpose to discuss the question further, but, as Mr Putnam remarks that "the entomologists' of Mr. Meehan's party were certainly unfortunate in finding so few insects," to state in justice to the entomologists of the party that their work was confined to the month of August in a single year, while Mr. Putnam gives the experience of a whole season. We certainly used every endeavor to make collections, even to setting up lights in canned fruit boxes at night, to allure the noctural species, and with very slender returns for the effort; and, as for collecting by day, in the previous article I make the statement that "after a few hours collecting, it was not an easy matter to find anything strikingly different from the dozen or so species secured in the collecting box." Perhaps fifty specimens of a common butterfly would make a sufficient abundance for the fertilization