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became about as scarce as it had been numerous before. accounts agree as to the sudden diminution of its numbers in the month of June, and so far as Missouri is concerned, it did not increase to any alarming extent during the rest of the year. The disappearance was, in many sections, so thorough that it is very questionable whether man and natural enemies should alone be credited with the cause. The spring was uncommonly dry and warm, and, so far, was favorable to the increase of the insect; but the summer drought and extreme heat which followed were quite unfavorable to its multiplication. Warm dry weather in spring is congenial to the growth and well-being of the larvæ as they swarm upon and devour our vines; but at a later stage of their lives when they have to enter the earth to undergo their transformations, a great many of them will undoubtedly die if the earth continues excessively dry and hot. They will, in short, be dried and baked to death. Those who have had large experience in breeding insects, and who understand the importance of coolness, and especially of moisture in the successful development of those which transform underground, feel perfectly warranted in such an inference, even though no systematic and accurate experiments have been made to test its validity. The extreme heat and dryness of the season, furnished a good opportunity to employ the sunscalding remedy, and it was fully shown that in an intense summer sun, the larvæ and even the beetles will very generally die if knocked from the vines on to the dry and heated ground, especially if the vines have been well hilled; and it is doubtless because the insect cannot thrive when the thermometer ranges near 100° F. that the southern columns of the spreading army extend far more slowly than the northern. Moreover, the past summer was not the first one in which the sudden disappearance of this insect under conditions of heat and drought has been noticed; for a similar state of things occurred in 1868, and Dr. Henry Shimer, of Mt. Carroll, Ill., then attributed such disappearance to the dryness of the season.* We are justifiable, therefore, in concluding that while dryness and warmth may be very pleasant and agreeable to the Colorado Potato Beetle in the spring or in the fall, they are nevertheless very destructive to it when intensified in the summer months.-C. V. RILEY, St. Louis.

SINGING MARYLAND MARMOT.- For the last forty years the fact of the common Maryland Marmot, or Woodchuck, being able to sing like a canary bird, but in a softer, sweeter note, has been quite familiar to myself, and others who could be brought forward as witnesses. Mr. Lockwood seems to have an ear to hear, which calls out for the thousandth time our statement. Mr. Audubon Jr. is the only zoological naturalist who would lend a respectful

* Am. Nat. vol. iii, pp. 91-99.

attention, to what profit we know not. For my part I am prepared to believe in any amount of animal capacity; not a tithe of what is already known can be safely communicated to this generation which we hope to show ere long. Neither" the whistling of the Woodchuck in its burrow," by which we understand is meant the surprise or alarm chuckle, nor the loud challenge or pseudo-bark of the Marmot of the Sierra Nevada Mts. etc., are at all alluded to in the following remarks.

When a lad we caught a very young Marmot. Mother prudently forecasting care, etc., stoutly refused to allow the pet. Knowing the warm side of a mother's heart, we wisely resolved to try a little finesse in order to gain parental permission, so my older brother and myself took a saucer of milk, for we were sure, if she saw it take hold with both infant paws like a little babe as we had, the victory was ours. Brother got all things ready, and I insisted she should just see it eat. Her kind heart yielded. "Wouldn't have it die for the world; it took hold of the edge with both hands so like a little child." It was raised. It had a seat in the little high chair at the children's table full oft. Its earnest and restless concupiscent purr as it scented sweet cake and fragrant viands was wonderful. At length it became as familiar as the family cat and finally burrowed under the doorstep. My impression is now, and has always been, that it was a female. I used to watch the pet very closely to see how it sang, as children are apt to do. There was a slight moving of the nostrils and lips and consequently whiskers with an air of unmistakable happy or serene enjoyment. I question much if this is altogether unknown to others, always excepting naturalists.-A. KELLOGG, M.D., San Francisco.

THE POSITION OF THE CENTRE OF GRAVITY IN INSECTS.-M. Felix Plateau has contributed an important memoir on this subject to the "Bibliothèque Universelle Archives des Sciences Physiques et Naturelles," of which the following is an abstract of the most important conclusions arrived at. (1.) The centre of gravity in an insect is situated in the vertical and medial plane which passes along the longitudinal axis of the body. (2.) It occupies a position almost identical in insects of the same species, the same sex, and in the same attitude. (3.) The exterior form of the body rarely permits the determination of the exact position of the centre of gravity without experiment. (4.) It does not occupy

the same position in the two sexes of one species. It is sometimes less and sometimes more to the rear in the females than in the males and its situation depends on the relations existing between the different dimensions of the individuals. (5.) While standing, the centre of gravity is placed at the centre of the abdomen, or in the posterior portion of the thorax, and usually in the centre of the length of the body. (6.) When an insect is walking its centre of gravity undergoes constant displacement about a mean point, but the distances of displacement are too small to be measured. (7.) The displacement of the centre of gravity when an insect passes from a state of repose to that of flight, cannot be ascertained except with those species where the wings lie folded on the back when in a state of repose. The displacement is horizontal, and from back to front. (8.) During active flight, the centre of gravity oscillates continually about a mean position which corresponds with the instants when the extremities of the wings pass the point of crossing of the S-shaped curve which they describe in the air. (9.) In aquatic insects it is nearer to the lower than to the upper surface of the body. (10.) During swimming, the movements of the posterior feet, acting like oars, determine the oscillation of the centre of gravity around a mean position, which answers to the position of the swimming feet placed at the middle of their course.-A. W. B.

OCCURRENCE OF THE SCISSOR-TAIL FLYCATCHER IN NEW Jersey. On the 15th of April last, a magnificent specimen of the "Scissortail" (Milvulus forficutus Swainson), was shot on the Crosswicks Meadows, five miles south of Trenton, N. J. The specimen was a male bird, in full health and feather; weighing two and one-half ounces avoirdupois, and measuring thirteen and one-half inches from the tip of the beak to the extremity of the tail. The bird, when captured, was busily engaged in picking semi-dormant insects from the bark of the trees; creeping about very much as is the custom of the Certhia Americana; and all the while, opening and shutting the long scissor-like tail. The stomach, on examination, proved to be full of small coleoptera, insects, eggs and flies. The specimen has been mounted, and will be forwarded to you in a few days.

On reference to the Pacific R. R. Rep. vol. ix, page 168, we find that Prof. Baird states that the allied species, Milvulus tyrannus

Bon. is entitled to a place in the United States Fauna, "on account of two specimens in New Jersey, captured, at long intervals; and one or two seen by Mr. Audubon in the South-west;" but no mention is made of this species we have taken here in New Jersey, being found farther north than Texas, where it is quite abundant. We have already called attention to the fact of New Jersey being "a sort of neutral ground in the matter of geographical distribution;" and the occurrence of this southern flycatcher is an additional proof of the fact; the more so, because it was taken when the weather was chilly, and during a spring more backward than any for the past twelve years. It might perhaps have been easier to account for the presence of this bird had the season been far advanced, or had a southerly wind or storm prevailed for a week or ten days previously; but the very opposite of all this had been in reality the case. - CHARLES C. ABBOTT.

HABITS OF THE YOUNG CUCKOO.- Mr. Hugh Blackborn, of Glasgow, Scotland, has published an account of a remarkable contest witnessed between the young of the cuckoo and of the common meadow pipit or titlark. The nests contained two pipits' eggs and one cuckoo's, the former of which were hatched first. Within forty-eight hours after the hatching of the cuckoo, it had expelled both the pipits from the nests and on their being replaced struggled about till it got its back under one of them, when it climbed backwards directly up the open side of the nest, and pitched the pipit from its back on to the edge, finally forcing it off. After this had been done several times, the pipits were at length found dead and cold, and when they were then replaced the cuckoo made no effort to eject them. The singular part of the affair is that the cuckoo was perfectly naked and blind, while the pipits had well-developed quills on the wings and back, and had bright eyes partially open; yet they seemed quite helpless under the manipulations of the cuckoo, which looked a much less developed creature. Each time, the cuckoo, though perfectly blind, made with unerring certainty for the open side of the nest, the only part where it could throw its burden down the bank on which the nest was placed.- A. W. B.

GREAT AUK (Alca impennis).- Professor James Orton in his article on the Great Auk, AMERICAN NATURALIST, Dec., 1869, page 540, says: - "Once very abundant on both shores of the North

Atlantic, it is now believed to be entirely extinct, none having been seen or heard of alive since 1844, when two were taken near Iceland."

While at Montreal in Aug., 1871, Mr. Alfred Lechevallier, a naturalist who has collected largely in Labrador, informed me of a specimen in his possession of this supposed to be extinct species. It was found dead in the vicinity of St. Augustin, Labrador coast, in November, 1870, by some Indians from whom Mr. Lechevallier obtained it while collecting there at the time. It was a male, and although in a very had state he preserved it and has recently sold it to a naturalist in France, who is to send it to Austria. Although it was a very poor specimen he realized two hundred dollars. RUTHVEN DEANE, Cambridge, Mass.

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ACTIVITY OF TROUT AND the American brook trout: active and, I was going to write

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it may be even so- - intelligent fish than the salmon or trout (English). Possibly they may have imbibed some of the national American sharpness.

consult them on the Alabama question."

I think I shall

I myself, while manipulating trout and salmon, at Orland, last November, learned that the former, although not a quarter the size of the salmon, was the more difficult fish to handle. This was partially owing to the plump shape of the trout, which caused the hand to slip off over the head or tail, and to a greater extent to its superior activity. The facility with which salmon yielded to manipulation was an agreeable surprise.-C. G. A.

THE CAROLINA HEMIRIAMPHUS. - My observations confirm and extend Dr. Coues' note (Am. Naturalist, vi., p. 49,) on this species. According to my note-book the fish was first seen by me Sept. 21, 1871, when several specimens were taken in a seine with mullet, and became very abundant about the last of the month. At this season vast schools of the Bluefish (Pomatomus saltator) were observed feeding upon the still vaster schools of the Hemirhamphus, which appear to be their favorite food. I have seen a Bluefish, when drawn into a boat, eject from its mouth as many as eight good-sized Hemirhamphi.-H. C. YARROW, M.D., U.S.A., Fort Macon, N. C.

POUCHED RAT (Perognatus fasceatus).- This is not very abundant in Texas. They dwell in burrows eight to ten inches deep,

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