82 T O R R E Y A 



AIarch 17. ]\Ieetixg at The Xew York Botanical Gardex. 



The meeting was called to order by the \'ice-President. Dr. Seaver, at 3 :30 p.m. 

 Attendance 36. The minutes of the preceding meeting were accepted. Dr. Whaley an- 

 nounced the death of Dr. Tracy Hazen on March 16th, in \\'aterbury. Conn. On a 

 motion by Dr. Stewart it was voted that the Secretary send the condolences of the Club 

 to the family of Dr. Hazen. Dr. Matzke stated that he had received from Dr. Moulton, 

 of the American Association for the Advancement of Science, a request for a summary 

 of the history of the Torrey Botanical Club. Dr. ^latzke said he would be willing to 

 prepare this summary which is to be published in the Journal of the Association with 

 the histories of other affiliated societies. The first scientific paper was presented by Dr. 

 Ernest Naylor who spoke on "Problems of Cellular Behavior during Regeneration." 



The author presents a brief discussion of some of the cell changes during early 

 stages of shoot and root formation on isolated plant parts during regeneration. The 

 multiplication and organization of cells during regeneration involves two funda- 

 mental types of cells morphologically. One is the meristematic type, which may or 

 may not be definitely organized into recognizable growing points. Such cells may be 

 variously located in leaf axils, nodal regions, leaf margins, woody structures, and 

 in other places. 



The other tj'pe is concerned with diflferentiated cells of the plant body which 

 undergo structural changes and become actively meristematic to produce the new 

 root and shoot primordia. Such de-dift'erentiation of vacuolate cells is described in 

 various tissues of a number of seed plants. The extent and limitations of such de- 

 differentiations in plant cells is briefly considered and some of the theoretical im- 

 plications pointed out. 



Dr. Whaley was the second speaker on the scientific program, and his topic was "In- 

 feriorit}^ Complexes in Plants." 



Recent work of Dobzhansky and others indicates that in natural populations 

 many detrimental recessive genes are accumulated. The number and relative potency 

 of these genes is dependent upon the population structure, which is a function of the 

 number of individuals and the type of reproductive mechanism. Under selection it is 

 also possible for unfavorable dominants to accumulate. Heterosis is the result of 

 masking of these deleterious recessives in some organisms, the result of heterozy- 

 gosity in others. Suggestions as to the nature of some of these deleterious factors 

 is found in excised root culture experiments. The roots of certain tomato lines show 

 a deficiency in ability to synthesize pyridoxine, others in the ability to synthesize 

 nicotinamide. Crosses between such lines produced vigorous hybrids under ordinary 

 field conditions. Hybrid vigor represents a return to an "optimum" phenotype rather 

 than any "super" phenotype. 



After a discussion of both papers, the meeting adjourned at 4:35 p.m. Then tea and 

 delicious refreshments, in keeping with the spirit of St. Patrick's Day, were served by 

 friends at the Garden. 



HOXOR M. HOLLIXGHURST, ReCORDIXG SECRETARY. 



March 27. Field Trip to The Xew York Zoological Park for the study of some animal 

 habits. Leader, Miss Nellie L. Condon, Director, Reptile Study Society of America. 

 Attendance 11. 



]\Iarch 28. Field Trip to Springdale. X. J., for limestone lichens. Leader. Mr. G. G. 

 X'earing. Attendance 4. Unusual forms found were: Acarospora muronim, Cyphelinm 

 figillare. and Physcia -rcuusfa. The last two were in fruit, and these fruiting forms 

 appear to be rare. 



April 4. Field Trip to Central Park, X"^. Y. to search for the trees mentioned in L. H. 

 Peet's book "Trees and Shrubs of Central Park" (1903). Leader, Dr. E. B. Matzke, 

 Columbia University. Attendance 25. Many of those present took an active part in the 



