Page:Popular Science Monthly Volume 46.djvu/582

 Preece. Louise. A System of Physical Culture for Public-school Work. Syracuse. N. Y.: C. W. Bardeen. Pp. 193, with Plates. $3.

Prosser, Charles S. Kansas River Section of the Permo-Carboniferous and Permian Rocks of Kansas. Pp. 54.

Saville, Marshal H. The Ceremonial Year of the Maya Codex Cortesianus. Pp. 4.—A Comparative Study of the Graven Glyphs of Copan and Quirigua. Pp. 13.

Sergi, Giuseppi. The Varieties of the Human Species. Principles and Method of Classification. Smithsonian Institution. Pp. 61.

Scripture, Edward W., Editor. Studies from the Yale Psychological Laboratory. Vol. II, November 1, 1894. Pp. 134. $1.

Shaler, N. S. Sea and Land. New York: Charles Scribner's Sons. Pp. 252. $2.50.

Smithsonian Institution. Annual Report of the Board of Regents to July, 1893. Pp. 763.

Stokes, Anson Phelps. Joint-Metallism. New York: G. P. Putnam's Sons. Pp. 198.

Thomas, Cyrus. Report of the Mound Explorations of the Bureau of Ethnology. Washington: Government Printing Office. Pp. 742.

Trotter, Spencer. Lessons in the New Geography. Boston: D. C. Heath & Co. Pp. 182.

Union College Inauguration of the Rev. Andrew V. V. Raymond, D. D., as Ninth President. Pp. 41.

United States National Museum. Baur, G. The Relationship of the Lacertian Genus Auricella. Gray. Pp. 8.—Lænnberg, Einar. Reptiles and Batrachians collected in Florida. Pp. 30.—Lucas, Frederick A. Anatomy and Affinities of Certain American Birds.—Ridgway, Robert. New Birds from Aldaba, Assumption, and Gloriosa Islands, collected by Dr. W. L. Abbott. Pp. 3.—Twenty-two New Species of Birds from the Galapagos islands. Pp. 16.—True, Frederick W. On the Rodents of the Genus Sminthus in Kashmir. Pp. 3. Diagnosis of some Underground Wood Rats. Pp. 3.—Diagnosis of New North American Mammals. Pp 3.—Verrill, A. E. New Species of Starfishes and Ophiurans, etc. Pp. 52.—Walcott, Charles D. Discovery of the Genus Oldhamia in America. Pp. 3.



A Discussion on Variation.—One of the most interesting sectional meetings of the British Association was one at which a series of papers was read dealing with questions connected with evolution and Darwinism, such as the real nature and cause of variation; the inheritance of acquired characters; the adequacy of natural selection to affect variation sufficiently to explain the great range of animal and plant structure. The first paper was by Prof. D'Arcy Thompson, on Some Difficulties of Darwinism, which was an attempt to deal with the third of these questions. Prof. Thompson suggested that the mechanical and mathematical principles of growth itself may have affected the form of animal life. He instanced the spiral shells of the nautilus and the conical eggs of the guillemot as probably deriving their shape from this principle. The second paper, by Prof. Riley, of Washington, dealt with the very interesting habits of the social insects—ants, bees, wasps, and termites—and showed how all the fresh knowledge accumulated since Darwin's time only corroborated his views, to the effect that in this case the "struggle for existence" of the colony as a whole must be substituted for that of the individual. An interesting point was made by Prof. Haycraft, to the effect that the true function of sex was to keep down variation—that by the combination of two individuals to form a new individual, a mean between the two was always obtained, and that in this way the race was kept constant; whereas, if the new individual could be produced from only a single parent, the limits of variation would be unduly extended. The other papers were by Mr. F. A. Dixey, on Some Fresh Points with Regard to Mimicry in Butterflies; and by Prof. Osborn, of New York, on Certain Variations met with in the Dentition of Fossil Mammals. Prof. Osborn showed how two teeth might come eventually to resemble one another closely, although the stages through which they passed had been widely different. The discussion which followed these five papers was of an animated character, and was participated in by a considerable number of members. Prof. Ray Lankester complained that most of the difficulties suggested had been long ago dealt with by Darwin himself, whose works were insufficiently studied by the younger generations of biologists. The discussion was finally summed up in a most lucid speech by Sir Edward Fry, who complained of the absence of clear issues, and of the consequent difficulty of forming a judgment on most of the points brought forward.

Cambodian Arithmetic.—The Cambodians have a quintesimal system of enumeration, yet they use nine digits and a cipher, and are able to count in practice about as if their system was decimal. Their methods of adding and subtracting are curious. Suppose one wishes to add the numbers 247,372, 53,723, 975,642, 278,383, the sum of which is 1,555,120. The Cambodian writes the first two numbers one above the other, draws a vertical line to the right of them, and 