80 RECORDS 



For Chairman and candidate for Vice-President, Professor 

 Bashford Dean. 



For Secretary, Dr. M. A. Bigelow. 



The Secretary was authorized by vote to cast a single affir- 

 mative ballot for these nominees. This was done, and the can- 

 didates declared duly elected. 



The scientific program consisted of a lecture by Professor 

 R. T. Jackson, of Harvard University, entitled " Localized 

 Stages in the Development of Plants and Animals." 



Summary of Paper. 



Professor Jackson showed that in the study of organisms 

 marked stages in development are found throughout life from 

 the young to adult and old age. Such stages are of the high- 

 est importance in phylogenetic studies as affording the key to 

 genetic relations. 



In addition to stages in the direct development, in many 

 plants and animals stages exist in localized parts throughout 

 the life of the individual, which are directly comparable to 

 stages found in the young, and to the adults of simpler and 

 more primitive fossil or living types. 



Localized stages are typically seen in organisms that grow by 

 progressive addition of similiar parts, in which the young or 

 growing part temporarily or permanently presents characters 

 which are closely comparable to characters found in the young 

 and adults of simpler types. 



In plants localized stages are seen in the distal and proximal 

 areas of the leaf, in suckers, "witches' brooms," late, sickly or 

 otherwise feeble growths, and, as shown by Cushman (^Anieri- 

 can Naturalist, November, 1902) in spring growths and leaves 

 below the flower. The last mentioned are particularly striking 

 as they present a localized senescence, repeating stages in in- 

 verse order of sequence from that seen in the seedlings. 



In animals localized stages are seen in the newly-added dorsal 

 inter-ambulacral plates of the corona of Strongyloccntrotns and 

 other sea-urchins. In young plates of the stem of some crinoids, 

 {Platycrimis, Pcntacriniis) and as pointed out by Grabau, in the 



