No. 17] FOURTH BIENNIAL REPORT 15 



which are large and conspicuous, and most of them have skel- 

 etons which are readily preserved. They are accordingly among 

 the forms which attract the attention of visitors to the shore. 

 Professor Coe's full descriptions of our species will be useful to 

 teachers, particularly in the towns along the coast, where the 

 pupils may easily become acquainted with these animals. One 

 genus of the echinoderms, the common starfish, is of great 

 economic interest, since it is one of the most destructive enemies 

 of the oyster. Professor Coe has given much attention to the 

 relation of the starfish to the oyster industry. The work is 

 beautifully illustrated with plates showing the aspect of the 

 living animals and others showing their anatomical structure. 



Miss Harvey's paper on Drainage and Glaciation in the 

 Central Housatonic Basin is a study of the changes in drainage 

 as the result of the events of the Glacial period. It was pre- 

 sented as a thesis for the degree of Doctor of Philosophy in 

 Yale University. It is the first instalment of a series of bulletins 

 bearing on the general subject of the Quaternary geology of the 

 state. 



WORK STILL IN PROGRESS 



/. Geology 



The geological investigations now in progress relate chiefly 

 to surface geology, or the study of the phenomena connected 

 with the work of the great ice sheet of the Glacial period. For 

 more than a generation geologists have recognized that the man- 

 tle of heterogeneous and unstratified drift covering most of 

 New England and the adjacent country is essentially the ground 

 moraine of a continental glacier; that the widely scattered 

 smooth, polished, and striated rock surfaces are the result of 

 erosion by such a continental glacier; and that the stratified de- 

 posits in the river valleys consist of the debris transported by 

 the glacier, sorted and redistributed by the action of water. But 

 it is within a comparatively few years that a more thorough 

 and detailed study has been given to these glacial phenomena. 

 Of the comparatively small amount of study that has been given 

 to the glacial geology of Connecticut, a considerable part has 

 been vitiated by preconceptions now known to be erroneous, 

 leading to false interpretations of observed facts, and preventing 

 due appreciation of phenomena which might have been observed. 



