Dearborn, A Laboratory-Course in Physiology Based on Daphnia etc. '2> s :> 



ersetzt werden. Aber das iindert doch an dem Prinzip nichts, dass 

 , jeder Lebensvorgang in irgendwelchem Grade von der Aufienwelt 

 abhiingen muss. Der Nachweis dafiir liisst sich nicht theoretisch, 

 auch nicht durch blofie Beschreibung der in der Natur zu beob- 

 achtenden Erscheinungen fiihren. Wir konnen vielmebr nur auf 

 dem Wege experimenteller Forschung das fundamentale Problem 

 angreifen, urn dadurch allmahlich einen wirklichen Einblick in die 

 innere Struktur der Pflanzen zu gewinnen. 

 Heidelberg, den 12. Marz 1912. 



Literatur. 



Backer, C. A. Plantes exotiques naturalisees dans Java. Ann. Jard. Bot. 1910, 



3. Supplement. 



Goebel, R. Organographie der Pflanzen I. Jena 1898. 

 Klebs, G. Uber die Rhythraik in der Entwickelung der Pflanzen. Heidelberger 



Akad., 1911. 

 Koorders und Valeton. Bidrage tot de Kennis der boomsoorten op Java. 



Pars I XII, 1894-1910. 



Schimper, F. W. Pflanzengeographie auf physiologischer Grundlage. Jena 1898. 

 Smith, A. U. On the internal temperature of leaves etc. Ann. Bot. Gard. Pera- 



deniya, Vol. Ill, 1906. 



Volkens, G. Laubabfall und Lauberneuerung in den Tropen. Berlin 1912. 

 Wright, R. Foliar periodicity of endemic and indigenous Trees in Ceylon. Ann. 

 ' Bot. Gard. Peradeniya, Vol. II, 1905. 



A Laboratory-Course in Physiology Based on Daphnia 



and other Animalcules. 



George V. N. Dearborn, M. D., Ph. D.. 



(From the Physiologic Laboratory of the Tufts College Medical and Dental Schools, 



Boston, Massachusetts.) 



In the course of the work in general elementary biology used 

 as an introduction and orientation to the instruction in human 

 medical physiology, it has become obvious that the time has come 

 for broadening, and not little, the practical phases of such instruc- 

 tion. Especially clear is it that already we instructors have wasted 

 too many months of our students' precious school-time in the study 

 of isolated and thus unnourished and abnormal mechanisms. One 

 thinks of course at once of the nerve-muscle preparation and of 

 the isolated heart and of strips of cat's bladder. These have long- 

 since served their day and now it is high time that we began to 

 take the view-point of the more advanced physical educationists, 

 and attempted to elaborate in our teaching the mode of working 

 of normal organs and tissues in normal animals. The scientific, 

 like the other, tendencies of the day is toward synthesis and uni- 

 fication, toward the study, more and more exact, of ,,things as 

 they are" . . . inseparable parts of an animal whose ultimate essence 



