566 



THE POPULAR SCIENCE MONTHLY. 



Preece. Louise. A System of Physical Culture 

 for Public-school Work. Syracuse. N. Y. : C. W. 

 Bardeen. Pp. 193, with Plates. $3. 



Prosger, 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 Com- 

 parative Study of the Graven Glyphs of Copan 

 and (^uirigua. Pp. 13. 



Sergi, Giuseppi. The Varieties of the Human 

 Species. Principles and Metho'^1 of Classifica- 

 tion. Smithsonian Institution. Pp. 61. 



Scripture, Edward W., Editor. Studies from 

 the Yale PsvchoJogieal Laboratory. Vol. II, No- 

 vember 1, 1894. Pp. 134. $1. 



Shaler, N. 8. 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. 19f'. 



Thomas, Cyrus. Report of the Mound Explora- 

 tions of the Bureau of Ethnology. Washington : 

 Government Printing Office. Pp. 742. 



Trotter, Spencer. Lessons in the New Geogra- 

 phy. Boston: D. C. Heath & Co. Pp. 182. 



Union College Inauguration of the Rev. An- 

 drew V. V. Raymond, D. D., as Ninth President. 

 Pp. 41. 



United States National Museum. Baur, G. 

 The Relationship of the Lacertian Genus Auri- 

 cella. Gray. Pp. 8. Lsennberg, Einar. Reptiles 

 and Batrachians collected in Florida. Pp. 30. 

 Lucas, Frederick A. Anatomy and Afflvities of 

 Certain American Birds. Ridgway, Robert. New 

 Birds from Aldaba, Assumption, and Gloriosa Is- 

 lands, collected by Dr. W. L. Abbott. Pp. 3. 

 Twenty-two New Species of Birds from the Gala- 

 pagos 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 :^. Verrill, A. E. New Species of 

 Starfishes and Ophiurans, etc. Pp. 52. Walcott, 

 Charles D. Discovery of the Genus Oldhamia in 

 America. Pp. 3. 



POPULAR MISCELLAIiY. 



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 varia- 

 tion ; 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 papci' was by Prof. D'Arcy Thompson, 

 on Some Difficulties of Darwinism, which was 

 an attempt to deal with the third of these 

 questions. Prof. Thompscm 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 ju-oljably 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 knowl- 

 edge 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 sub- 

 stituted for that of t'^.o in Zividual. An in- 

 teresting 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 w'ere 

 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 charac- 

 ter, and was participated in by a considerable 

 number of members. Prof. Ray Laukester 

 complained that most of the difiiculties sug- 

 gested had been long ago dealt with by Dar- 

 win himself, whose works were insufficiently 

 studied by the younger generations of biolo- 

 gists. 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. 



Canibfldian Aiititmetic.^The Cambodi- 

 ans have a quintesimal system of enumera- 

 tion, 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. Sup- 

 pose 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 



