164 RECORDS. 



2. Middle oil, or carbolic oil. 



3. Heavy oil, dead oil, or creosote oil. 



4. Anthracene oil or green grease. 



5. Pitch (remains in the stills). 



These five products were taken up in detail, and about one 

 hundred drugs, perfumes, etc. were exhibited, the method of 

 derivation of the substances being explained. 



S. A. Mitchell, 

 Secretary. 



SECTION OF BIOLOGY. 



February 9, 1903. 



Section met at 8:15 P. M at the American Museum, Vice- 

 President Dean presiding. The minutes of the last meeting 

 were read and approved. 



The following program was offered : 



W. A. Cannon, Cytological Studies of Variation in 

 Hybrids. 



Bashford Dean, Past and Present Study of Zoology 

 IN Japan. 



H. F. Osborn, On the Primary Divisions of the Rep- 

 tilia into Two Subclasses. 



Summary of Papers. 

 Dr. Cannon's paper, was based upon his studies of hybrids 

 of cotton plants, and discussed the relation between the matura- 

 tion mitoses in hybrids and the variation of the hybrid race. Two 

 forms of mitosis occur in fertile hybrids. One of these is the 

 normal type, which occurs in pure races and may be supposed 

 to give rise to reproductive cells of pure descent. This is the 

 form in hybrids between closely related parents (monohybrids), 

 and probably forms the basis for the regular reversion in them. 

 The other type of mitosis is irregular. It is suggested that this 

 kind of maturation mitosis may organize cells of mixed descent, 

 and if found in hybrids from parents rather distantly related, 

 would constitute the basis for such mixture of the characters of 

 the pure parents as occurs in these hybrids. However, after 



