NOTES AND LITERATURE 



ANIMAL STRUCTURE AND HABITS 



Professor R. Hesse and Professor F. Doflein have undertaken 

 the preparation of a general work on the structure and habits 

 of animals, of which the first volume 1 has just appeared. This 

 volume deals in a most complete way with the animal as an 

 independent organism and the authors reserve for subsequent 

 treatment the consideration of animals in relation to their en- 

 vironment. After an introduction which deals with life, proto- 

 plasm, the cell, animals and plants, the theory of descent, etc., 

 the subject matter of the volume follows in four books dealing 

 with the statics and mechanics of the animal body, its metabo- 

 lism, powers of reproduction and inheritance, and the nervous 

 system and sense organs. A final section takes up the relation 

 of the parts of the animal to the whole. As a sample of the 

 thoroughness with which the subject is treated the contents of 

 the first book may be taken. This part ..pens with an account 



by a consideration of these aspects of the multicellular forms. 

 The skeleton in the invertebrates and vertebrates is fully de- 

 scribed. The power of animals to float in water and in air is next 

 considered, and the remainder of the book is given over to a 

 presentation of locomotion proper. This includes movements 

 by cilia and by muscles and under the head of muscular loco- 

 leeches, etc., by wriggling as seen in snakes, eels, etc., and by 

 means of lever appendages. This last section includes swimming 

 by appendages, springing, running, climbing and flying, and the 

 last of these is discussed in relation to insects, bats and birds. 

 The treatment is rich in examples and abounds in well-con- 



tions of the book are equally full and exhaustive. 



The subject matter, though often complicated, is treated in an 



