THE i'j:()(ij:J'Jss of sciem'e. 



89 



diiugliter ami a youngor son and I lie 

 most common family of Ihifc would 

 be two (laiigliters and a younger son. 

 Apparently no sucli statistics have been 

 collected or even proposed. 



The alleged causes of the small fami- 

 lies in France do not seem to obtain in 

 New England. It is extremely improb- 

 able that all parents should volun- 

 tarily limit the size of families; the 

 decreasing family nuist be in part due 

 to physiidogical causes, which may be 

 individual or racial. Individual causes 

 may be late marriage, especially of 

 women, school life and other unhy- 

 gienic conditions, or an inhibition ex- 

 erted by intellectual and other interests 

 outside the family. 



Racial sterility is certainly possible. 

 It seems to conflict with the prin- 

 ciple of natural selection, as fertility 

 might be supposed to have a high se- 

 lective value. Natural selection, how- 

 ever, can only select, it can not pro- 

 duce variations. If size of head is 

 more variable than size of pelvis and is 

 equally important for survival, the in- 

 creasing difficulties of childbearing are 

 not inexplicable on the theory of nat- 

 ural selection. If sterility increases, 

 we must assume that the conditions 

 of the environment have altered too 

 rapidly for variation and natural selec- 

 tion to keep pace with them. Indeed 

 the existing conditions may be due in 

 part to our interference with natural 

 selection. The decreasing death rate 

 on which we pride ourselves may in 

 part be responsible for the decreasing 

 birth rate. When children who can 

 not be born naturally or can not be 

 nursed survive, we may be producing 

 a sterile race. No statistics in regard 

 to miscarriages are at hand, but there 

 is good reason to believe that they in- 

 crease as the number of children de- 

 creases. There is no positive proof of 

 race senescence in man. On the con- 

 trary we know that the Italians and 

 the French Canadians have large fami- 

 lies, though there is as much reason 

 for them to auffer from racial exhaus- 



linii as llic inlial)i1aiils of l'"i-aiicc, and 

 (lie ( liinese seem to lie in no danger of 

 extermination. iJut we know tiiat ani- 

 mals bred for special traits tend to i)e- 

 come infertile, and f-election foi- our 

 civilization may have the same re- 

 sult. J'hysicists tell us that the earth 

 may be uninhabitable in twenty mil- 

 lion years; it may be uninhabited by 

 1 man in twenty centuries. 



77/ /v FIELD COLUMBIAN MUSEUM. 

 TiiK Field Columbian' Museum, of 

 Chicago, lias now been in existence for 

 ten years and has during this period 

 made important progress. It was or- 

 ganized in 1893 at the close of the ex- 

 position, from which it received its 

 building and some of its collections. 

 The following year the name ' Field 

 (. olumbian Museum ' was adopted, 

 owing to the generous gifts made by 

 Mr. Marshall Field. The building 

 erected for temporary purposes is grad- 

 ually falling to pieces, and it is said 

 that Mr. Field will provide a new build- 

 ing, which will surpass that of the 

 American Museum of Natural History 

 in New York City and the new building 

 for the U. S. National Museum, for 

 which congress has recently appro- 

 priated three and a half million dol- 

 lars. The report of the director of tlie 

 Field Columbian ;Museum for last year 

 describes important increases in the 

 collections and improvements in their 

 arrangement. The collections have been 

 largely secured through sixteen ex- 

 peditions sent to dift'erent parts of 

 North America. Ethnology seems to 

 have been specially favored, nine ex- 

 peditions under the charge of Dr. 

 George A. Dorsey and other members 

 of the staflF having made extensive col- 

 lections in Oklahoma, New Mexico, 

 Montana, California and Alaska. Two 

 collections were also purchased, one 

 of which contains fourteen hundred 

 specimens from the Tlingits of Alaska. 

 In the department of botany the her- 

 barium has been augmented by over 

 twenty thousand sheets, and the de- 



