MUSEUM OF COMPARATIVE ZOOLOGY. 11 



With the return of Assistant Professor Jackson, after a year's 

 leave of absence, the courses in Pal ae zoology were resumed. Both 

 Zoology 9a and Zoology 9b had graduate students only. 



At the suggestion of the Committee on Instruction, certain 

 courses — in which the laboratory work consisted in the inves- 

 tigation of a separate problem by each student in the class — 

 were transferred from the middle group of' studies to that which 

 is designated as " primarily for graduates." These were courses 

 10a, 106, 11a, 116, 15 and 16. 



The nature of the courses designated as Zoology 10a and 10b — 

 conducted by Assistant Professor Castle — is succinctly set forth 

 in the pamphlet of the Department for 1906-1907. The lectures, 

 owing to the rapid advance of knowledge in the subjects treated, 

 require frequent revision. Some of the topics studied by the 

 students in these courses were color and size inheritance in rats 

 and rabbits, and the physiological differences between different 

 color varieties of Guinea-pigs. Some of the results obtained will 

 be incorporated in future publications. 



Following the plan adopted the previous year, the subject matter 

 of Zoology 13, by Professor Parker, was so divided that the new 

 half-course, Zoology 14, deals with muscular and sustentative 

 tissues, while Zoology 13 is now to be limited to epithelial and 

 nervous tissues. The lectures of Course 14, though based on a 

 part of those of Course 13, have been expanded and are essentially 

 new. 



In Zoology 16, also by Professor Parker, each student was 

 assigned a special topic for investigation. Of these, two have 

 yielded results that are in preparation for publication. Two 

 students studied the same subject in this course as that on 

 which they were working in Zoology 20. Five students took 

 the course in Radcliffe ; two of them wrote theses, and three 

 elected to do the laboratory work. Of the latter, two obtained 

 results that will be offered for publication. 



Of the eleven men who began researches in Zoology 20, two 

 withdrew early in the year, one to do his work in another depart- 

 ment of the University, the other for financial reasons. Seven of 

 those who continued their work w r ere under the direction of Pro- 

 fessor Mark, one under Professor Parker, and one under Professors 

 Mark and Parker jointly. Three students presented theses that 

 were accepted, and passed the examinations for the degree of 

 Ph.D. ; the degrees were conferred at Commencement in June, 



