270 The Ohio Naturalist. [Vol. VIII, No. 4, 



quality it is none the less accurate. This shows that the book 

 was written by men who are familiar with the art of teaching. 

 The clear statements, the logical development of the subject, and 

 the rigid scientific accuracy are silent testimonials to the ability 

 of the authors. The same authors have prepared a laboratory 

 manual to accompany this text. It is useless to say it possesses 

 the same merits as the text. It gives the student ample instruc- 

 tions without reaching all of his conclusions for him. This 

 manual causes the student to work and makes him think while 

 he works." J. C. H. 



Date of Publication, February 15, 1908. 



