304 ANNALti NJEW YORK ACADEMY OF SCIENCES 



former has already tapped the ischiadic iu the popliteal fossa. Whether 

 the femoral arise before the inferior epigastric from the external iliac, or 

 vice versa, or whether they arise simultaneously, has not been ascertained 

 from lack of suitable material. Should the femoral arise prior to the 

 inferior epigastric, it would by no means invalidate the fact that tlie 

 external iliac is not merely the root of the femoral, but a separate vessel 

 having a developmental history quite peculiar to itself. The external 

 iliac is the second branch (in time of development) of the hypogastric, 

 tlie ischiadic (inferior gluteal) being the first. Before the femoral arises 

 from the external iliac there are four branches of the hypogastric, viz,, 

 ischiadic, external iliac, internal pudenal, and superior gluteal. 



Mr. Bagg stated that the plan of the experiment is to measure indi- 

 vidual differences in behavior in various strains of mice; to determine 

 the extent to which an animal which departs from the average in one 

 direction will depart in others; to measure the resemblance in families 

 and in lines of descent, and to determine the degree to which kinds of 

 conduct can be established in family lines by selection. Eesults ha^^e 

 been so far obtained for over two hundred mice that were tested in two 

 types of mazes. Striking individual differences have been noted for 

 various tasks, and an apparent resemblance between mice belonging to 

 the same litter was found to be nearly twice as great as between un- 

 related individuals. There appears to be a considerable difference among 

 strains of mice, and the sex differences, if any, are slight. 



Eight generations of mice have been so far obtained, and the genetics 

 of the problem has resolved itself into a study of the offspring obtained 

 from mating animals that are quick to learn with those slow to learn, 

 those that are quick with quick ones, and slow with slow ones. The 

 effects of inbreeding and outbreeding are also being tested. 



Mr. Nichols stated that the comparative development of the groups of 

 Ostariophysous fishes in Africa and related families indicates that the 

 Mormyrids are a remnant of an earlier ichthyfauna, and that of the more 

 modern groups the Catfishes came first, then the Characinge; the in- 

 vasion of Carps is very recent and still in progress. 



In comparing the condition found in South America the absence of 

 Carps is accounted for by recent isolation of that continent by sea, the 

 development of the Gymarchids by absence of similar Mormyrids, and the 

 diversified development of Catfishes by supposing them to have been the 

 first fresh-water family in the field. 



The Section then adjourned, 



William K. Geegoey, 



Secretary, 



