140 CARNEGIE INSTITUTION OF WASHINGTON. 



treatment, as will also two widely removed genera in a subfamily. 

 If these investigations indicate the possibility of connecting certain 

 chromosomes with definite groups of characters, efforts will be made 

 later to carry out the difficult task of hybridizing the species that 

 offer the best material for study. 



William Patten, Hanover, N. H. Grant No. 157. /vr studies 

 relating to the origiyi of vertebrates. $500- 



Abstract of Report. — By means of the grant to aid in procuring 

 material for the study of the origin of vertebrates, many Devonian 

 fishes were obtained from New Brunswick. 



The specimens of Bothriolepis canadensis were more perfect than 

 any others that have ever been found. They will furnish the neces- 

 sary data for a complete restoration in great detail of a typical rep- 

 resentative of the Ostracoderms, one of the oldest and most primitive 

 subdivisions of the Chordata known. 



The structural features shown by this new material will necessi- 

 tate the removal of the Ostracoderms from the Agnatha, separate 

 them farther than ever from the true fishes, and will raise them to 

 the rank of a new and independent class. 



Raymond Pearl, University of Michigan, Ann Arbor, Mich. Grant 

 No. 125. For an investigation by statistical methods of correlation 

 ifi variatioji. $500 • 



Abstract of Report. — The grant was expended as follows : (a) In 

 the purchase of calculating machines, measuring instruments, and 

 other minor apparatus. (3) In procuring clerical assistance in the 

 reduction of data, (r) In purchasing literature to which access 

 could not otherwise be had. 



During the year Dr. Pearl and students under his direction have 

 been engaged in work along the following lines : 



(i) The variation in the weight of the human brain and the cor- 

 relation between this and other characters of the body. A paper on 

 this subject has been completed and is submitted with the report. 



(2) The effect of environmental changes of known quality and 

 measured intensity on variation and correlation in the Protozoa. 



(3) The correlation between the same and different characters in 

 conjugating individuals of Paramecium (homogamy). 



(4) The variation and correlation in certain of the component parts 

 of the character "stature" in man. 



(s) The correlation between differentiated homologous organs and 

 undifferentiated homologous organs in the crayfish. 



