PREFACE 



These outlines were first written for use by students 

 in the large laboratory classes in embryology in Kansas 

 State Agricultural College, and represented the work 

 done (by those classes) during one term (twelve weeks). 

 After they were used for two terms, they were revised, 

 parts rewritten, and some sections added. It is thought 

 that the use of an outline is the simplest means of secur- 

 ing more or less uniformity in the work of the several 

 classes and, at the same time, of encouraging the devel- 

 opment of the individuality of both the student and the 

 teacher. The course is not intended as an independent 

 one, but is planned to supplement recitation and lecture 

 work so that the student may obtain by observation a 

 general knowledge of the processes and phenomena of 

 development. The material suggested for use in the 

 course is such that, if it is not already at hand, it may be 

 obtained v^-ith a minimum of difficulty. The work is 

 meant to be so arranged that if time does not permit 

 the use of all parts of the outlines, some sections may be 

 omitted and at the same time preserve the continuity of 

 the course. 



The author is indebted to various authors for sug- 

 gestions. Those suggestions have been so modified from 

 time to time that it is scarcely possible to give credit to 



