HAECKEL AND THE NEW ZOOLOGY 



of arthropoda, of which the crawfish is a member. 

 Then, perhaps, the professor calls the students about 

 him and gives a demonstration of the curious phe- 

 nomena of hypnotism as applied to the crawfish, 

 through which a living specimen, when held for a few 

 moments in a constrained attitude, will pass into a 

 rigid "trance," and remain standing on its head or in 

 any other grotesque position for an indefinite period, 

 until aroused by a blow on the table or other shock. 

 Such are some of the little asides, so to speak, with 

 which the virile teacher enlivens his subject and gives 

 it broad, human interest. Now each student turns to 

 his microscope and his individual dissection, and the 

 professor passes from one investigator to another with 

 comment, suggestion, and criticism; answering ques- 

 tions, propounding anatomical enigmas for solution 

 enlivening, vivifying, inspiring the entire situation. 



As the work proceeds, Professor Haeckel now and 

 again calls the attention of the entire class to some par- 

 ticular phase of the subject just passing under their 

 individual observation, and in the most informal of 

 talks, illustrated on blackboard and chart, clears up 

 any lurking mysteries of the anatomy, or enlivens the 

 subject with an incursion into physiology, embryology, 

 or comparative morphology of the parts under obser- 

 vation. Thus by the close of the session the student 

 has something far more than a mere first-hand knowl- 

 edge of the anatomy of the crawfish though that in 

 itself were much. He has an insight also into a half- 

 dozen allied subjects. He has learned to look on the 

 crawfish as a link in a living chain a creature with 

 physiological, psychological, ontological affinities that 



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