1874.] 117 [Gray. 



polar forces"; that "studying the subject in the most general 

 manner, there are striking resemblances between the distri- 

 bution of matter capable of assuming a polar condition, and 

 free to move around a magnet, and the distribution of mat- 

 ter around the nervous axis of an embryo." That this is not 

 one of those vague conceptions by which many speculators 

 set about to explain that of which they know little by means 

 of that of which they know less, but that he had striking 

 parallelisms to adduce, the close of this striking paper shows. 



The subject of fore and hind symmetry, thus brought 

 directly under notice, had been broached by Dr. "Wyman 

 several years before. He returned to it the year following, 

 in his very important morphological paper, " On Symmetry 

 and Homology in Limbs," read to this Society in June, 1867, 

 and published in the Proceedings of that date. It is inter- 

 esting to observe with what caution and restraint. he handled 

 this doctrine of " reversed repetitions," which has since been 

 freely developed by one of his pupils who has a special pre- 

 dilection for speculative morphology, Prof. Bart Wilder. 



Prof. Wyman's " Notes on the Cells of the Bee," in the 

 "Proceedings of the American Academy" for January, 1866, 

 is a characteristic specimen of his way of coming directly 

 down to the facts, and making them tell their own story. I 

 could not recapitulate his results much more briefly than he 

 records them in his paper. I need not recall to you how 

 neatly he made this investigation, and represented some of 

 the results, filling the comb with plaster-of-paris and then 

 cutting it across midway, so that the observations might be 

 made and the cells measured just where they are most nearly 

 perfect ; and then printing impressions of the comb upon the 

 wood-block, he reproduces on the pages of his article the* 



