PREFACE 



A CERTAIN broadening of scope of the practical work customary among 

 us for students in animal physiology has become desirable, and has seemed 

 so for some time past in the opinion of not a few. A number of facts 

 fundamental to physiology can be seen by the student very readily and 

 appropriately in the frog. But other facts there are, of great value and 

 interest especially to the future practitioner of medicine, which can be better 

 displayed and more easily obtained in the mammalian preparation. Although 

 that preparation as available for a class-student is merely a carcase, the 

 circulatory activity which it retains for the time being, and the temporary 

 survival of many of its glandular and muscular tissues and of its simpler 

 nervous structures, render obtainable from it under suitable precautions 

 a number of reactions which can be studied with extreme advantage by the 

 student for himself. The exercises detailed in the following pages consist of 

 experiments of that kind. Several of them are repetitions, simplified in 

 accordance with the limits of the preparation and of the student's experience, 

 of famous observations which in the hands of the masters who fii-st made 

 them marked distinct advances in natural knoAvledge. The particular ex- 

 periments chosen are of course not the only ones which might have been 

 selected. In such a choice each teacher will to some extent have his own 

 predilections. The mammalian preparation decapitate or decerebrate is 

 capable of serving many uses for practical class-instruction. The particular 

 experiments included here are, however, all such as experience actually 

 proves the student to be well able, with ordinary care on his part and some 

 supervision on the part of his teacher, to accomplish successfully for himself. 

 The actual performance by the student of some few such main experiments 

 gives him, I am convinced, a better insight into their general significance 

 and into the problems they touch than does any mere inspection at a 



