proceedings: biological society 67 



a common base may produce repeatedly the same or similar morpho- 

 logical and physiological results." 



Nmnerous examples were given and illustrated on the board, of 

 characters of structures and characteristics of habit which were paralleled 

 over and over again in connected and disconnected genera, subfamilies, 

 and families. He also illustrated characters and characteristics which 

 were paralleled in all of the species of a single genus and in connected 

 genera, groups, subfamilies, and famiUes, and said further: 



"Thus we see that parallel modification in morphological and physio- 

 logical elements is an important factor to be considered in taxonomy. 

 It is evident from a comparative study of the various systems of classi- 

 fication that the failure of taxonomists to fully realize its importance 

 has led to many erroneous conclusions and much confusion. 



"In conclusion, it seems to me that we have two fundamental ques- 

 tions to be answered in regard to the origin, evolution, and classification 

 of organisms. 



"1. Are the taxonomic characters and characteristics of the species, 

 genus, family, order, class, and kingdom the result of phylogenetic descent 

 from a single ancestral nucleus, thru natural selection and the inheritance 

 of selected characters f or 



"2. Are they the result of phylogenetic descent from many nuclei 

 thru natural selection and natural parallelism? 



"I am inclined to the belief that an affirmative answer to the second 

 question would be more nearly in accord with natural law." 



President Nelson exhibited a series of mammal skins in pairs 

 similar in outward appearance but widely different in structure and 

 classification, showing the parallelism of shape and color. 



0. C. Oberholser discussed parallel development as illustrated 

 in birds. He showed a large series of specimens in which resemblances 

 in form and color were very striking. 



J. W. GiDLEY pointed out the difference between parallel and con- 

 vergent development. 



Messrs. Lyon, Hay, Baker, Bartsch and Gill took further part in 

 the discussion. 



Dr. Hopkins closed the discussion by stating that the illustrative 

 material presented by Messrs. Nelson and Oberholser had sho^vn 

 only one phase of the principle — homomorphic parallelism, which is not 

 correlated with evidences of natural affinity, but is repeated in more 

 or less widely separated groups and species, while the other — homol- 

 ogous parallelism — is parallelism of structure, color, habit, etc., which 

 is correlated wdth evidence of natural affinity and is repeated in the 

 same species or in connected genera or larger groups. 



The 34th annual meeting and 5 18th regular meeting was held De- 

 cember 13, 1913, President E. W. Nelson in the chair and twenty-eight 

 persons present. 



The annual reports of officers were received. The election of officers 



