RECORDS 99 



symmetrical. The greater the departure from the normal form 

 the smaller is the ratio of radially symmetrical individuals. 

 Thus only 11.2% of the medusae having five canals are irre- 

 gular, while 30-33% of those with four or six canals are irre- 

 gular; in medusae with seven or three canals 50% are irregular, 

 while 100% of those with two or eight canals are so. The lips 

 show a decided tendency to revert to the ancestral number of 

 four, at intervals of 90°, but the canals, on the contrary, incline 

 toward the higher numbers. We have here a medusa which is 

 continually producing radially symmetrical sports, and is initiat- 

 ing, so to speak, what might become new species were con- 

 ditions favorable. 



On comparing the variations of P. pentata with those of E. 

 folleata or Eucope, one is struck with many remarkable family 

 likenesses. This is especially true in the former comparison. 

 Similarity of the variations, the likeness of their abnormalities, 

 in these closely-related forms, indicates apparently a race kinship. 

 The abnormal young of P. pentata appear to survive fully as 

 well as normal individuals, and abnormal medusae mature their 

 gonads quite as commonly as the normal forms. The former 

 are not weeded out by natural selection, yet they have not suc- 

 ceeded in establishing new types of medusae. 



In discussion of Dr. Mayer's paper, Dr. MacDougal spoke of 

 a sport of Populiis tremuloides, discovered by Dr. Britton, in 

 which the irritability to gravity of the leaves had been reversed 

 so that they now pointed downwards. The reversal appeared 

 in the buds. New plants propagated by grafting retained the 

 positive geotropism of the leaves. It was also stated that the 

 ** weeping" varieties of certain trees were usually produced in 

 this way. Henry E. Crampton, 



Scc7^etary. 



SECTION OF ANTHROPOLOGY AND PSYCHOLOGY. 



February 15, 1901. 



Section met 8:15 P. M., Professor J. McK. Cattell presiding. 

 The following program was offered : 



