RECENT PROGRESS IN PHYSIOLOGY. 445 



clew furnished by the study of the higher animal. This truth seems to 

 have been early recognized during the progress of the science. In the 

 old time observers such as Spallanzani, with but a moderate amount 

 of accumulated knowledge behind them and a host of problems before 

 them, with but few lines of inquiry as yet definitely laid down, were 

 free to choose the subjects of their investigation where they pleased, 

 and in the Avide field open to them prodded, so to speak, among all 

 living things, indifferent whether they possessed a backbone or not. 

 But it soon became obvious that the study of the special problems of 

 the more highly organized creature was more fruitful, or at least more 

 easily fruitful, than that of the general problems of the simpler forms; 

 and hence it came about that inquiry, as it went on, grew more and 

 more limited to the former. But an increasing knowledge of the laws 

 of life as exemplified in the differentiated plienomena of the mammal 

 is increasingly fitting us. for a successful attack on the more general 

 phenomena of the lowly creatures possessing little more than that 

 molecular organization, if such a phrase be permitted, which alone sup- 

 plies the conditions for the manifestation of vital activities. And 

 though it may be true that in all periods men have from time to time 

 labored at this theme, I think that I am not wrong in saying that the 

 last dozen years or so mark a distinct departure both as regards the 

 number of researches directed to it, and also, what is of greater moment, 

 as regards the definiteness and clearness of the results thereby obtained. 

 One has only to look at the results recorded in the valuable treatises 

 of Verworn and Biedermann, whether obtained by the authors them- 

 selves or by others, to feel great hope that in the immediately near 

 future a notable advance will be made in our grasp of the nature of 

 that varying collection of molecular conditions, potencies and changes, 

 slimy hitherto to the intellectual no less than to the physical touch, 

 which we are in the habit of denoting by the more or less magical word 

 protoplasm. And perhaps one happy feature of such an advance will 

 be one step in the way of that reintegration which men of science 

 fondly hope may ultimately follow the differentiation of studies now so 

 fierce and attended by many ills; in the problems of protoplasm the 

 animal physiologist touches hands with the botanist, and both find that 

 under different names they are striving toward the same end. 



Closely allied to and indeed a part of the above line of inquiry is the 

 study of the physiological attributes of the cell and of their connection 

 with its intrinsic organization. This is a study which, during the last 

 dozen years, has borne no mean fruits; but it is an old study, one which 

 has been worked at from time to time, reviving again and again as new 

 methods offered new opportunities. Moreover, it will probably come 

 directly before us in our sectional work, and therefore I will say nothing 

 more of it here. 



Still another striking feature of the past dozen years has been the 

 advance of our knowledge in regard to those events of the animal body 



