THE ORDER AMONG ANIMAL TYPES 127 



Suggested Readings 



Parker, T. J., and Hasvvell, W. A.: Textboo\ of Zoology. 1 volumes. 



The Macmillan Company, 1927. 

 Hegner, R.: College Zoology. The Macmillan Company, 1931. 

 Lancaster, E. R.: Treatise on Zoology. 8 volumes. The Macmillan 



Company. 

 Guyer, M. F.: Animal Biology. Appendix. Harper and Brothers, 193 1. 

 Hegner, R. W.: Invertebrate Zoology. The Macmillan Co., 1933. 

 Borradaile, L. A., and Potts, F. A.: Invertebrata. Cambridge University 



Press, 1932. 



