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SCIENCE 



[N. S. Vol. XXXVIII. No. 972 



even his intimate friends did not know his 

 conclusions on important matters until 

 after they had appeared in print. 



He was primarily a naturalist and had 

 no patience with experimental work done 

 by men who had no intimate acquaintance 

 with the animals studied; he characterized 

 such experimentalists as " Versuchstiere, " 

 and hated their so-called ' ' problems. ' ' Later 

 he came to be an enthusiastic advocate of 

 the experimental method as a supplement 

 to, but not as a substitute for, observational 

 studies, and in his new laboratory he had 

 made extensive provision for such work. 



He was a very rapid worker, and as he 

 wrote up his results at once and published 

 them without delay he always had several 

 papers in press, and at his death it was 

 found that he had left but little work un- 

 finished. One notable exception is a text- 

 book of cytology for which he had com- 

 pleted eleven chapters, leaving the rest of 

 it in outline. It is to be hoped that this 

 valuable work will be completed and pub- 

 lished. In it he manifests that unusual 

 mastery of the literature of the subject 

 which was one of his leading characteris- 

 tics, and which particularly fitted him for 

 such a task. 



As a teacher and organizer he was suc- 

 cessful in a rare degree. His enthusiasm 

 was balanced by critical judgment, and he 

 was an inspiring and exacting teacher. 

 His intimate acquaintance with the ma- 

 terials and literature of zoology, his posi- 

 tive and clear-cut opinions on most sub- 

 jects, a sense of humor and a certain pic- 

 turesqueness of language made him a most 

 instructive and entertaining lecturer; also 

 he had marked ability to direct and stimu- 

 late graduate students in research work. 

 His plans for the development of zoology 

 at the University of Pennsylvania were 

 very comprehensive, including almost 

 every great branch of the science. 



During the last three or four years of 

 his life, his greatest work was the new 

 zoological laboratory at the University of 

 Pennsylvania, which will ever be a monu- 

 ment to his energy, ability and foresight. 

 He and his colleagues worked on the plans 

 almost a year, and all details of construc- 

 tion, equipment and furniture were care- 

 fully planned. Almost another year was 

 spent in constructing the building, and the 

 labor of moving into it and getting things 

 into working order had scarcely been fin- 

 ished when he was stricken with his last 

 illness. He deeply regretted the loss of 

 time from his researches which the con- 

 struction of the building involved, but as 

 the plans and building were completed 

 rapidly, this lost time was reduced to a 

 minimum, and he expected to enjoy for 

 many years the facilities which he had so 

 laboriously secured. 



Although he often spoke of the time lost 

 from his researches while the building was 

 on hand, it is nevertheless a fact that dur- 

 ing those years he published almost as 

 many papers as during any previous period 

 of equal length, while the number of papers 

 published during the last year of his life 

 was as gTcat as in any other year, with a 

 single exception. He realized that the new 

 laboratory must be justified by the research 

 work done in it, and the responsibility of 

 "making good" rested heavily upon him. 

 Undoubtedly during those last few years 

 he worked beyond his strength, and when 

 the fatal disease attacked him he had not 

 resistance enough to overcome it. 



He was stricken with pneumonia on 

 February 15, 1912, and after a long strug- 

 gle, in which hope many times alternated 

 with despair, he succumbed on March 19, 

 only a few days after his thirty-ninth 

 birthday. His death, which occurred on 

 the opening day of the celebration of the 

 centenary of the Academy of Natural Sci- 



