6 RECORDS 



The following program was then offered : 



Franz Boas, The Relation between the Variability of 

 Cells and that of Organisms. 



Gary N. Calkins, Degeneration in Paramcecium and so- 

 called Rejuvenescence without Conjugation. 



Henry E. Crampton, Natural Selection in Samia cecropia. 



Summary of Papers. 



Professor Boas, in his paper, which has been printed in full 

 in Science for Januaiy 3, 1902, established the following con- 

 clusions : "(i) The elements of organisms are more variable 

 than the organisms themselves. (2) The elements of organisms 

 \2.ry in correlated groups. (3) The characteristics of the varia- 

 bility of an organism depend upon the correlations of its con- 

 stituent elements, so that a knowledge of these correlations will 

 enable us to determine the characteristics of the variability of 

 the organism." (4) It was also pointed out that skew distribu- 

 tion of variations does not necessarily indicate selection, or 

 instability of type, but may occur in stable forms. 



Dr. Calkins presented the history of two individuals, A and 

 B, of Paranuvchiui caudatum, from different localities, which 

 were isolated February i, 1901. These were fed on twenty- 

 four hour hay-infusion and the number of divisions recorded at 

 periods of from one to three days throughout the year, one 

 individual being isolated each time. Conjugation occurred for 

 the first time, among the extras, in May. This period was fol- 

 lowed, in July, by well-marked degeneration of both A and B, 

 which went so far that nearly all of the stock was lost. The 

 survivors were stimulated to renewed activity by treatment with 

 extract of lean beef After three months of normal and active 

 divisions, another period of conjugation occurred. This again 

 was followed by degeneration and again the cultures were saved 

 by treatment with beef-extract. At the present date (Jan. 13), 

 A is in the 416th generation and B in the 375th generation, 

 and no conjugation has taken place in the direct line of the cul- 

 tures. Thus far the experiments have yielded the following 

 results: (i) Paraviaxiuju unquestionably passes through more 



