MUSEUM OF COMPARATIVE ZOOLOGY. 



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was continued as heretofore. Each year there is a noticeable 

 increase in the effacement of our glacial deposits. It is hoped 

 that, by carefully recording the occurrence of these superficial 

 phenomena, the field work of our students will preserve the 

 knowledge of an interesting district, the natural features of which 

 are rapidly vanishing. The same advance of culture upon the 

 natural ground in the environs of Boston has rendered it desirable 

 to extend the regular field excursions to more distant points than 

 were formerly visited. ' Half-day excursions were therefore made 

 again this year to Attleboro, Plainville, and Pondville, Mass. Dur- 

 ing the April recess, a voluntary excursion was made to Martha's 

 Vineyard for the purpose of examining the terminal moraine on 

 that island, and of making a section of the Gay Head cliffs. Mr. 

 Francis Noyes Balch, a student in the course, succeeded in veri- 

 fying the reported occurrence of a substance resembling amber in 

 the Gay Head section. The teaching collection was farther en- 

 riched by a collection of lignite from the non-marine Cretaceous 

 of the island, and by characteristic lithological specimens from the 

 Cretaceous, Neocene, and Pleistocene beds. In the lectures, more 

 attention than usual was given this year to the light which the 

 alluvial deposits of modern great rivers throw upon the structure 

 and origin of certain ancient fresh water or non-marine deposits 

 of the Carboniferous and Triassic Periods. The subject of joints 

 and fractures in rocks was illustrated by new and undescribed 

 material largely collected on the excursions made with students 

 in this course. 



The course in Glacial Geology (Geol. 16) was taken by two 

 men. In addition to the instruction given, some time was spent 

 with one student in elaborating a classification of glacial depos- 

 its, paying especial attention to the recognition of the moraine 

 terrace or ice-contact slope at the rear of sand plains and mo- 

 raines as a key to the understanding of the relations of the 

 departing ice sheet to the drift laid down about it. Excursions 

 were made tending to show the widespread distribution of this 

 feature in Southern New England. Trips were also conducted to 

 Mt. Monadnock, N. H., to the Falmouth moraine and the Queen's 

 River boulder belt in Rhode Island, in the interest of students 

 in this course. 



In addition to the instruction in the above courses, work was 

 done by Mr. Woodworth with the aid of Mr. F. C. Schrader, in 



