PRESERVATION OF FRESH-WATER POLYZOA.-Mr. Stewart explained to the South London Microscopical and Natural History Club that he had succeeded in killing polyzoa with the tentacles expanded by adding a few drops of the best French brandy to the water they were living in. They were overcome by the liquor, without drawing in their plumes.

CRYSTALLIZATION OF METALS BY ELECTRICITY.- This has been studied under the Microscope by Philip Braham, Esq. His apparatus is described in the "Monthly Microscopical Journal," for Dec. 1871.

CONJUGATION IN RHIZOPODS.

J. G. Tatem, Esq. has observed what seems to be an instance of this hitherto unnoticed, though not unsuspected, process in the case of a common Amœba.

PHOTOGRAPHING BY BLACK-GROUND ILLUMINATION.-Dr. Woodward has obtained good high-power photographs (x 1000) of objects illuminated by Mr. Wenham's truncated lens.

CLEANING DIATOMS.- Dr. Maddox cleans and bleaches diatoms by immersion in a solution of chlorate of potash and hydrochloric acid.

MICROSCOPICAL STRUCTURE OF THE WAX OR BLOOM OF PLANTS. An interesting study of this familiar substance occurring on leaves and fruits, by Prof. De Bary, is given in the "Botanical Zeitung," with some thirty beautiful illustrations. The wax does not appear to be a simple coating over the surface, as though it might have been laid on liquid with a brush, forming a continuous layer. It is seen to be rather a dense forest of minute hairs of wax; each one sitting with one end upon the epidermis and the other either rising up straight or rolled and curled among its neighbors. This matting of waxen hairs often becomes so dense that when examined from the surface it presents to the microscope the appearance of a continuous layer, while a carefully made section of the leaf, or skin of the fruit, shows its true structure. The question from what part of the epidermis or subepidermal tissue does the wax come, is most beautifully and clearly answered. He says that in the cell-contents there cannot be discovered the slightest trace of wax, and the statement that the chlorophyll is partly made of wax is totally erroneous. The locality

in which it can be first detected is the cuticle and the cuticularized elements of the epidermis cells.—T. D. B.

NOTES.

PROF. Agassiz read a notice of the life and character of Dr. E. Holbrook of Charleston, S. C., before the Natural History Society of Boston, Oct. 18, 1871. He remarked that:

"The death of Dr. Holbrook has been deeply felt by a very large circle of friends, and by those who are acquainted with the history of science during the last fifty years. But highly as he was appreciated by all to whom he was personally known, and by his scientific peers and colleagues, America does not know what she has lost in him, nor what she owed to him. A man of singularly modest nature, eluding rather than courting notice, he nevertheless first compelled European recognization of American science. by the accuracy and originality of his investigations. I well remember the impression made in Europe more than five and thirty years ago, by his work on North American reptiles. Before then, the supercilious English question, so effectually answered since, Who reads an American book?' might have been repeated in another form, Who ever saw an American Scientific Work?' But Holbrook's elaborate history of American Herpetology was far above any previous work on the same subject. In that branch of investigation Europe had at that time nothing which could compare with it.

6

Born near the close of the last century, in 1796, Dr. Holbrook entered upon his career as a student at a moment of unusual activity in scientific research in Europe. Although his birth occurred at Beaufort, S. C., he received his early education at the north. His father, himself a New England man, brought him, when only a few months' old, to Wrentham, Mass. There he grew up, and though his after fortunes led him back to his birthplace and the greater part of his life was passed in South Carolina, he remained warmly attached to the home of his boyhood. From school he went to Brown University, and after completing his college course there he studied medicine in Philadelphia, and subsequently prac tised for a short time with a physician in Boston; but he took a larger and more comprehensive view of his profession than that of the special practitioner, and he went abroad to seek a more general scientific culture. He went through the Medical School at Edinburg, and then travelled on the continent, making himself familiar with methods of study and practice there. But perhaps nothing in all his European journey had greater influence upon his future life than his stay in Paris, where he worked at the Jardin des Plantes, and became intimate with some of the leading scientific men of the day. He formed relations then which ended only with

life, such as his friendship with Valenciennes, with Dumeril, Bibron and others.

On his return to America he was called to the Professorship of Anatomy in the Medical School of Charleston, S. C. From this time Dr. Holbrook, although he became an eminent practitioner in the city which had adopted him, was even more distinguished as a teacher of human anatomy, and finally renounced practice to devote himself to his professorship. Clear, simple and straightforward as a teacher, intimate with the most advanced systems of thought and instruction, he inspired his students with a love of nature, and made them indeed, in not a few instances, naturalists and men of science, as well as physicians. His pupils are among the most cultivated men of the South. His lovable personal qualities endeared him to them, and many of his students lost in him not only a revered teacher, but a well beloved friend."

THE Officers of the Boston Young Men's Christian Union, recognizing the importance of scientific studies, and the need of encouraging scientific tastes, have determined to establish in the rooms of the Union a Natural History cabinet. Their object in providing such a collection, is to foster the growing taste for science among the young men of Boston, and to open a new source of instruction and amusement to the members of the Union.

The cabinet will be in charge of Mr. F. W. Clarke, and contributions to start it are earnestly solicited. Specimens should be sent, carefully packed, to the care of F. W. Clarke, B. Y. M. C. Union, 300 Washington Street.

In compliance with a repeatedly expressed desire, the Smithsonian Institution has determined to make more frequent transmissions to Europe of exchanges of books, and announces that it is prepared to receive parcels at any time, with assurance of speedy delivery, at least to the more important addresses, upon the following conditions, which must be strictly observed:

1. Every package, without exception, must be enveloped in strong paper, and secured so as to bear separate transportation by express or otherwise.

2. The address of the institution or individual for whom the the parcel is intended must be written legibly on the package, and the name of the sender must be written in one corner.

3. No single package must exceed the half of a cubic foot in bulk. 4. A detailed list of addresses of all the parcels sent, with their contents, must accompany them.

5. No letter or other communication can be allowed in the par

cel, excepting such as relates exclusively to the contents of the package.

6. All packages must be delivered in Washington free of freight and other expenses.

Unless all these conditions are complied with the parcels will not be forwarded from the Institution; and, on the failure to comply with the first and second conditions, will be returned to the sender for correction.

Specimens of natural history will not be received for transmission, unless with a previous understanding as to their character and bulk.

OUR Contemporary, the "Revue Scientifique" (Jan. 13, 1872, p. 679) in analyzing a paper by one of the editors of this journal, has made several mistakes, one of which we might notice. It says "Mr. Packard rejects in consequence the idea of Fritz Müller and Brauer that the primitive insects had all leptiform larvæ, and were not afterwards modified to produce insects with eruciform larvæ." On the contrary he agrees with the opinion of Müller and Brauer that the earliest insects were those with an incomplete metamorphosis, quoting with approval Müller's note to that effect.

In a previous number (Sept. 23, 1871, p. 300) Dr. Packard is made to say "that the king crabs are nearer the Trilobites than Pterygotus." He has never said this, but on the contrary follows Mr. Woodward in uniting the king crabs with the Eurypterida, of which Pterygotus is a member; considering the king crabs as on the whole much more remotely allied to the Trilobites than to the Eurypterida.

ENTOMOLOGISTS will be pleased to learn that Mr. R. II. Stretch of San Francisco is now ready to begin the publication of "Illustrations of North American Zygænidæ and Bombycidae" in which he hopes to be able to figure all the North American species. The first plate, containing eight species of Alypia, six of Ctenucha, one Scepsis and a Psychomorpha are in the hands of Miss Peart of Philadelphia to be lithographed. Mr. Stretch proposes to figure the species as he can procure them, and so to arrange the letter press that it can be bound in proper order. The book will be uniform in size with the transactions of the American Entomological Society. The value of such a work will largely depend on the aid rendered to Mr. Stretch by museums and individuals, and

we trust he will receive every encouragement. At any rate many interesting and rare Californian species will be figured, which will make the work of much value to students.

THE second edition of the "Guide to the Study of Insects" having been exhausted, a new and improved edition will appear late this month. Several new plates and cuts will be added, and an appendix, bringing the work down to the latest date. price will be reduced to five dollars.

The

A NATURAL History Society is flourishing at Natick, Mass., and is now growing rapidly, having a membership of seventy. Its museum is gaining accessions, and already needs more room for cases.

It is proposed to add a department of Science to the Executive Branch of the Government. It is to be composed of the Storm Signal Corps of the army, the Lighthouse Board, and the Coast Survey Bureau of the Treasury, and the Hydrographic Bureau of the Navy.

A COMMUNICATION to the Corporation of Brown University was recently presented from Colonel Stephen T. Olney, making a munificent offer of his herbarium and books on botany, on condition that a suitable building should be provided for their reception. It was referred to a committee.

DR. W. Stimpson writes us from Key West, Florida, under date of January 15, "To-morrow I leave here in the U. S. Steamer, "Bibb" Capt. Robert Platt, to run a series of dredgings between Cape St. Antonio (Cuba) and Cape Catoche (Yucatan), and I anticipate most interesting results, as Capt. Platt has had three years' experience in deep sea dredging with Pourtales. We expect to get into two thousand fathoms at least."

EXCHANGES.

Botanical microscopic objects (mounted) also herbarium specimens of mountain and sea-shore plants, desired in exchange for U. S. herbarium specimens.—REV. H. G. JESUP, Amherst, Mass.

Diatomaceous Material, fossil or recent, desired in exchange for mounted dia toms from Western localities.-H. H. BABCOCK, 11 18th St., Chicago, Ill.

Azolla and other Hydropterides (living specimens) desired in exchange for fresh water algae or mounted microscopic objects.-T. D. BISCOE, 321 George St. Cincinnati Ohio.

Microscopic Fungi, mounted or unmounted, desired in exchange for microscopic slides or herbarium specimens.-C. E. HANAMAN, 103 First St., Troy. N. Y.