March 8, 1895.] 



SCIENCE. 



257 



cast light ou the populatiou of the Missis- 

 sippi Valley and Atlantic slope of the Un- 

 ited States at a date anterior to that of the 

 tribes found there resident by the first ex- 

 plorers. He presents the question temper- 

 ately and free from the fantastic notions 

 which one generally anticipates in this in- 

 vestigation. His results may be briefly 

 stated. 



Beginning with the ' mound builders,' he 

 points out numerous reasons for consider- 

 ing them the immediate ancestors of the 

 present Indians ; going further into their 

 identification, he decides that the ancestors 

 of the Cherokees were the mound builders 

 of the Ohio Valley. The original seat of the 

 Huron-Iroquois family he locates north of 

 the Great Lakes, and that of the Algon- 

 quian family somewhere to the south of 

 Hudson's Bay, where the Crees are still 

 found speaking a pure and ancient dialect. 

 These two mighty stocks moved slowly 

 southward, driving the mound builders 

 from the Ohio, and penetrating into Vir- 

 ginia. There they met the Dakotas, whom 

 they destroyed, except the small tribes of 

 the Tuteloes and Catawbas. The Gulf 

 States were peopled l)y the Muskoghean 

 tribes from the south-west. The debated 

 qui'stion whether there was a ' rough stone ' 

 or paheolithic age in the United States, he 

 answers, from the evidence before him, in 

 the negative. 



galton's method of isogens. 



Mr. Galton is fertile in the application of 

 new methods to anthropologic data. In a 

 recent article in the Journal of Statistics he 

 applies the method in use among meteorolo- 

 gists to define lines of equal barometric 

 pressure, to data of natality. His so-called 

 ' isogens ' are analogous to the isobars of the 

 weather maps. They are lines of equal 

 birth-rate forming a constant derived from 

 the two variables, the age of the father and 

 that of the mother. 



Bj' this ingenious and simple process he 

 reaches some curious results. One is the 

 unexpected law of natality, " That the 

 sums of the ages of the parents are con- 

 stant ; in other words, that the birth-rate is 

 determined by the joint ages of the father 

 and mother. The dirt'erence between the 

 ages of the two parents is of no account 

 whatever in nine-tenths of the total num- 

 ber of marriages." Only in the obvious 

 case where the wife is older than the hus- 

 band and is approaching the limit of the 

 child-bearing age, is this law at fault. An- 

 other odd fact developed by this method is 

 that a woman approaching somewhat closely 

 the limit of the child-l)earing age, say about 

 thirty-five or thirty-eight, is more fertile 

 with a man of her owai age than with one 

 who is younger ; though it is admitted cer- 

 tain social reasons may help to this result. 



Like all of Mr. Galton's articles, this one 

 will be found admirably presented and well 

 worth study. 



D. G. Brixton. 

 University of Penxsvlvaxia. 



CUKREXT XOTES OX PHYSIOGB.irHY (II.). 



SIXTH INTERNATIONAL GEOGRAPHICAL 



CONGRESS. 



The Sixth International Geographical 

 Congress is to be held in London from July 

 26th to August 3d, 1895, under the auspi- 

 ces of the Royal Geographical Society. An 

 invitation circular has lately been issued, 

 stating the general plan of the Congress, 

 the conditions under which tickets of mem- 

 bership can be obtained, the program of 

 subjects for discussion, and a most compre- 

 hensive list of honorary officers, honorary 

 general committeemen, and committees in 

 charge of various divisions of the subject 

 proposed for discussion. An extended ex- 

 hibit of geogi-aphical materials will l)e held 

 in connection with the Congress, which 

 altogether promises to be a most attractive 

 reunion. The invitation circular can be 



