of the abdomen is always visible even with the surface. Thus respiration is carried on, I suppose. The sensation is a dull itching; and if the person is much occupied the entrance is very likely to be effected unperceived; at least, it was often so in my own case. Then a day or two may, perhaps, elapse before any considerable annoyance is felt. This consists of a tenderness about where the insect is, with an itching there or thereabouts. The nigua may be in the great toe, and you will rub or scratch the second or the third; or it may be in the bottom of the toe and the itching be felt at the root of the nail. This is one of the peculiarities of the irritation caused by this almost invisible pest. Another peculiar effect of the puncture, or lodgment, of the nigua is, that, after it is completely extracted the irritation continues the same for a day or two thereafter, especially if the part be scratched or rubbed. If now it be neglected very likely it may not be felt again till after several days, and when it has become nearly or quite gravid, when a slight soreness or a tenderness is sure to be experienced.

It is exceedingly rare that any ill-effect results from the extraction of a single nigua, or of a few, unless the party should be peculiarly predisposed to disease. The reason why the negroes are so much troubled by them is their own neglect, stupidity, laziness, or the toughness of the skin, or all combined. Their feet frequently are in a most disgusting condition, and the extirpation of the animals is not unattended with danger of ulceration, sometimes resulting in lockjaw. — CHARLES Wright.

BIRDS' EGGS.-I will give a few hints taken from Mr. Wheelright and others. The utmost importance is to be placed upon the proper identification of the specimens. To every bird's leg attach a label noting sex ( for female, ♂ for male), date of capture and locality. Blow the eggs with a blow-pipe. Make but one hole and that on the side. Above the hole write the initials of the collector, and under it the number. (It is well also to put Baird's Smithsonian number on each). All the eggs in one nest should have the same number.

Suppose I take my first nest, Canada Jay, 15th March, with three eggs, I mark all three eggs, say No. 5, and keep a small note-book ruled thus:

A printed label, with the name of the bird, looks very neatly. In the case of small birds always preserve the nests, as they are often more interesting and valuable than the eggs themselves. All the eggs of the same nest, and the nest, being numbered the same, by a reference to the little note-book the identification of any eggs (even if they get mixed) is very easy, and the history of any specimen can be ascertained. If an egg has

been sat on very long this will be found a good process to clean out the embryo: Make a little larger hole than usual in the side, pick out as much of the young bird as you safely can, and then blow water into the egg with a blow-pipe; let it stand for some days in a dark drawer or box; keep repeating this process about every third day, gradually blowing more water into the shell, and picking a little out, till the whole of the embryo has decayed and is removed. This is a safe and sure way for a rare and valuable egg. I often put large eggs where the Cabinet-bug (Dermestes) can get into them, and clean out any foreign matter adhering to the shell.-G. A. BOARDMAN.

HABITS OF EARTHWORMS.*. -Last spring (and this) I was led to watch the common earthworms in my garden, and on the plot of grass saw their manner of feeding. I was within ten inches of their bodies. I saw one prepare to feed on a young clover leaf from a clover stock; he kept his tail secured to the hole (as a base line) in the ground, by which he retreated quicker than the eye could follow him. Finding all quiet he came again. Within a few inches of my eye the pointed head of the worm changed, and the end was as if cut off square. I then saw it was a mouth. He approached the leaf, and by a strong and rapid muscular action of the rings of the whole body drew the leaf and one inch of the tender stock into his mouth, and then by a violent muscular action drew the whole stock of young and tender clover towards him, and when all the substance was sucked out he let the plant go and it (the stock) flew back to its former place. The leaf and stem were entire, but looked as though it had been boiled. I then laid a small piece of cold mutton down, and he appeared to feast both on the fat and lean, dragging them after him, as his powers of suction could not act as well as if they had been held like the clover leaf. I also find that when the male and female are together they appear as one worm of double the size.-R. P. KNIGHT, Philadelphia.

HONEY BEE KILLED BY ASCLEPIAS POLLEN.-I found Bidens frondosa in Morris County, N. J., in the summer of 1867, constantly with petals. In the same summer, in continuation of my observations on the manner of fertilization of Asclepiads, I repeatedly found honey bees entangled, or rather entrapped by the glands. I found them dead; starved to death, I suppose, or exhausted with their efforts to escape. At other times they either got free themselves or with a little help. I found them most abundantly in the neighborhood of Peekskill, N. Y., being much assisted in my search by Rev. Mr. Morris, and his brothers, of Lake Mohegan. No insect of any size was found thus entrapped, and only a very few small diptera, which I looked upon as interlopers, or accidents. The bee having the pollen mass on his leg alights on the flower, and as he draws his leg up, in reaching over to the other side, brings the blade of the pollen mass into the stigmatic cleft, where it adheres, separating from the stalk, which still remains attached to the insect's leg. This

*Communicated by the Smithsonian Institution.

stalk then catches in the groove of the gland, and draws out a new set of pollinia. Passing to a new flower (or another part of the same perhaps) the same process is renewed, and I have found strings of the glands and shafts thus attached to each other, particularly on the old flowers of A. incarnata. On one occasion I caught an insect, on A. incarnata I believe, which had drawn out the pollen of this species by means of the shaft of A. purpurescens. At that time I had not a set of the various pollinia to compare the two with, and I sent the specimen to that enthusiastic botanist, W. W. Denslow, who had made a set, and he verified my supposition. This incident would show that the same insect had within a short time visited more than one species of Asclepias. Do insects visit flowers promiscuously, or do they, as one guest, confine themselves to one species? I have watched honey bees on a bed of hyacinths and thought that the same set confined themselves to the same color. Is there any rule in the matter? My lamented friend, W. W. Denslow, was engaged with me in working up the subject of the fertilization of Asclepiads by insects, when death cut short his studies. I had urged him to write to you on the subject but he had points which he wished first to settle, particularly how the hair of the insect is held in the gland of the stigma.-W. H. LEGGETT, New York.

ANOTHER DOUBLE EGG.-A short time since I visited a family, the lady of which had broken a number of eggs to fry for breakfast a few moments before I had arrived, and in the inside of one of the eggs was a small, perfectly formed egg, about the size of a pigeon's egg, which was given to me, and which I now have. I removed the contents, consisting of albumen alone. The egg from which it was taken contained the usual contents, white and yolk.-R. L. WALKER, M. D., Penn.

Six cases of double eggs are noticed on page 50 (Vol. ii) of the NATURALIST.-EDS.

THE KINGFISHER IN WINTER. -I noticed this day (December 11, 1868), about noon, a kingfisher perched on a tree, making his usual wild notes, and looking for his game; below him was a small stream, a spring which does not freeze over in the coldest weather and in which fish can be seen. The day mentioned was very cold, 20° below zero. I had supposed that those birds went to the South long before this. Can they endure our Northern cold weather? Where do they keep themselves in our very cold nights?-HENRY DAVIS, Houston County, Minn.

A few kingfishers remain all winter in New England.-Eds. EXTERNALLY AND INTERNALLY PARASITIC ACARI.-M. Guérin Méneville notes, in a letter to the French Academy, the sudden appearance of innumerable acari (Tyroglyphus fecula) on his potatoes. In less than eight days these little arachnidans became so abundant as entirely to cover the potatoes, and form a seething mass. He is at a loss to account for their remarkable and sudden appearance.

Mr. Charles Robertson, Demonstrator of Anatomy in the University of Oxford, has lately described a form of acarus found inside pigeons, chiefly

amongst the connective tissue of the skin, the large veins near the heart, and on the surface of the pericardium. In some respects the acarus described agrees with Sarcoptes, but has an extraordinary maggot-like appearance. The discovery of an external parasite inside an animal, in such numbers as Mr. Robertson records, is very remarkable. Colonel Montague found such acari in the gannet, and Mr. Robertson has since found them in the pelican. It is exceedingly difficult to account for their appearance. Are they undergoing a normal phase of their existence, or have they been accidentally introduced in the cases recorded, and found the habitat a favorable one?- Quarterly Journal of Science, London.

ORNITHOLOGICAL. In the September (1868) NATURALIST Mr. Kedzie gives an instance of the "breeding peculiarities" of the Golden-winged Woodpecker (Colaptes auratus), in which he states that he obtained thirty-three eggs from one of their nests, and calls upon any of the readers of the NATURALIST to surpass it.

In the spring of 1865, while in Maryland, I obtained twenty-two eggs from the nest of our common House Wren (Troglodytes ædon), and doubtless would have got more had not the nest been broken up. Mr. George Hensel, taxidermist of this city, also informs me that he once obtained twenty-eight eggs from the nest of a Kingbird (Tyrannus Carolinensis). Although the number of eggs obtained in the two cases mentioned are not equal to those got by Mr. Kedzie, yet considering the size of the dif ferent birds I think that I am a little ahead of him.

Last spring, while in Florida, I found the Bluebird (Sialia Sialis) breeding there. Can any of our ornithologists inform me whether it has ever been found breeding so far South before?-C. H. NAUMAN, Lancaster, Pa.

REGENERATION OF LIMBS.-M. Milne-Edwards has communicated to the French Academy some new results of M. Philippeaux's experiments on the subject of the regeneration of limbs. The author's early experiments made on reptiles prove that if the limbs of a newt be cut off, the scapula or ilium being left behind, the limbs will be reproduced, but that if the scapula is removed the limb is never reproduced. He has now been experimenting on fishes, and has proved that this is true. If the fin-rays of a fish be cut off they will be reproduced; but if the part which is homologous with the scapula be removed, no reproduction will take place. Scientific Opinion.

THE MARYLAND MARMOT (Arctomys monax Gmel.), more popularly known in this locality by the common name of "Groundhog," is still tolerably abundant in the southern districts of Lancaster County, Pa.; but I never knew they were so prolific, at least I have seen nothing on record that indicates anything like the fecundity of a female specimen captured in Drumore Township, on the 24th of April last. This subject, before she was killed, brought forth five naked cubs, and afterwards our taxidermist found that her matrix contained six more, making eleven. These young were all entirely nude-not a particle of hair on any of them and a sort of film over their eyes. They may have been prema

turely brought forth through the excitement incidental to capture, as these animals are usually very shy, going abroad mainly during the night. A curious fact in reference to these young marmots is, that one of them was immersed in cold water for two hours without destroying life. They were fully three inches in length, and I should judge from their size, weighed about an ounce and a half.-S. S. RATHVON, Lancaster, Pa.

THE SALT LAKE EPHYDRA.-In the April number of "Hardwicke's Science-Gossip," is figured an "animal from Salt Lake," which the correspondent and editor seem unable to identify. It is undoubtedly the larva of Ephydra, of which the fly and puparium have been figured in the NATURALIST, Vol. II, p. 278, and a short account given of the occurrence of other species in the salt-works in Germany, the Equality salt-works, Gallatin County, Illinois, the salt Lake Mono, California, and the coast of Labrador and Massachusetts, where it lives in salt or brackish water. -A. S. P.

THE SPIDER AND MUD-WASP. - Mr. Thomas Affleck, of Ingleside, Mississippi, in a letter to the late Dr. T. W. Harris, dated July 20th, 1848, and preserved in the Library of the Boston Society of Natural History, relates the following curious incident:-I noticed a singular incident the other day, confirming a strange fact (to me) in the insect world. A very large spider was attacked by one of the small blue mud-wasps, or dirtdaubers, not half its size, and on the ground. The spider seemed much alarmed, and managed to fend off his antagonist and escaped at a rapid pace, doubling and winding. The wasp seemed to have lost him for several seconds, but presently it circled round like a well-trained fox-hound, and on striking the trail ran it closely through all the doublings and windings of the spider, overtaking and attacking him again. This was repeated two or three times, the wasp clearly trailing the spider, as a hound would a fox. At length he succeeded in stopping the spider, when a capital fight ensued, lasting at least a minute. The spider had no chance with his enemy, who soon stung him to death, losing a leg only during the fight. After resting a few moments the wasp circled around again, evidently selecting a smooth path, along which he dragged with much difficulty his bulky prey. The moment he met with an impediment, dropping the spider, he circled round again, and invariably chose a smooth path. Where did instinct cease, and reason begin here? Were you aware that insects followed a trail, from the scent, in this way?

VARIATION Of Bluebirds' EGGS.-I found on the 17th of May a nest of eggs so peculiar that I wish you to know of them. I was hunting east of here when I saw a bluebird enter a small hole in an old stump. I noted her carefully, and also recognized a male near by. When I found my hand would not enter, and that the bird would not come out, I pushed the stump over, tearing away a part, and not till then did the bird come out. I am certain that it was a female bluebird, but every one of the five eggs was pure white. I also noticed that, unlike the woodpecker's, the bottom of the cavity was well bedded with grass; strictly a bluebird's