MUSEUM OF COMPARATIVE ZOOLOGY. 19 



work of this kind, Professor Raymond has had many thin sections 

 of sedimentary rocks prepared as the nucleus of a collection to 

 illustrate the various phenomena of sedimentation. 



The following were added to the palaeontological collections 

 during the year: by donation, a collection of Rhizopoda formerly 

 belonging to Professor Charles H. Wing, given by Mrs. Wing 

 through Prof. C. H. White, and three drawers of specimens of 

 limestone and fossils from Bermuda, given by Dr. W. P. Haynes; 

 by purchase, fourteen drawers of rocks and fossils from the Pearse 

 collection, and seven specimens of graptolites from Frederick 

 Braun. 



In Economic Geology, Professor Graton gave Geology 10, 

 Geology 18, and Geology 206. In Geology 10, the general course 

 on Ore deposits, the plan of giving laboratory work as a required 

 part of the instruction, proved successful and will be continued. 

 No regular summer course was offered, but two graduate students 

 devoted the entire summer to field-work under Professor Graton's 

 direction. 



Because of the unusual opportunities offered, most of the re- 

 search in Economic Geology continues to focus on problems con- 

 nected with the secondary enrichment investigation. Dr. Joseph 

 Murdoch's thesis, Microscopical determination of the opaque 

 minerals, is published as a textbook and has already found a wide 

 distribution. Mr. D. H. McLaughlin, candidate for the doctor's 

 degree, has, under direction, continued laboratory and summer field- 

 work relating to the occurrence and significance of the mineral 

 bornite. Mr. A. Wandtke is expected to submit results of his 

 work in Alaska during last summer on ore occurrence in the Nikolai 

 greenstone as one of two theses for the doctor's degree. Mr. E. H. 

 Perry, though having fulfilled residence requirements for the 

 doctor's degree, spent the winter and spring months in the labo- 

 ratory and part of the summer in the field in continuation of his 

 research on rock alteration accompanying ore deposition. 



With the aid of advanced students, reports based on micro- 

 scopic study of rocks and ores were made for important mining 

 companies in Alaska, Siberia, Peru, and Transvaal, as well as in 

 various parts of this country. It appears that actual, practical 

 problems of this kind appeal greatly to the students' interest and 

 are, of course, of unequalled value for purposes of instruction. 



During the year Prof. W. W. Atwood conducted at Harvard 

 the courses, Geography 1, 2, 6, 16 and 20a; and at Radcliffe, the 

 courses Geography 1 and 6. 



Assisted by Prof. F. H. Lahee of the Massachusetts Institute of 



