CONTENTS, 



LECTURE PAGE 



I. The Variations and Mutations of the Introduced 

 Sparrow. Passer Domesticus. Hermon C. 

 BUMPUS I 



II. Cleavage and Differentiation. E. G. Conklin . 17 



III. TJie Centrosomes of tJie Fertilized Egg of Allolo- 



bopJiora Foetida. Katharine Foot ... 45 



IV. The Methods of Palaeontological Inquiry. W. B. 



Scott 59 



V. TJie Physiology of Excretion. Arnold Graf . 79 



VI. Some Neural Terms. Burt G. Wilder . . . 109 



VII. A Classification of the North American Taxaceae 

 and Coniferae on the Basis of the Stem Struc- 

 ture. D. P. Penhallow 175 



VIII. TJie Selection of Plant Types for the General 



Biology Course. James Ellis Humphrey . 193 



IX. TJie Rate of Cell-division and tJie Function of tJie 



Centrosome. A. D. Mead 203 



X. Coalescence Experiments upon the Lepidoptera. 



Henry E. Crampton, Jr 219 



XI. Some of the Functions and Features of a Biologi- 

 cal Station. C. O. Whitman 231 



