6 The Pleistocene Deposits of Sankoty 



siderable number of specimens were collected, especially of the 

 smaller mollusks. A number of crab claws were also obtained. 

 Some of the results of the collecting trip were published by the 

 writer in the American Geologist for September. A number of 

 species not previously recorded were found, as well as others 

 which are rare. 



II. THE EXPOSED CLIFF SECTION. 



That the cliff section shown at Sankoty Head has changed since 

 the first mention of it by Desor and Cabot, is very certain. At 

 that time and for many years following, the waves attacked the 

 base of the cliff, gradually eating their way into it and causing a 

 complete exposure of the beds from top to bottom. Since the 

 time of the earliest observers there has come about, what may be 

 considered a radical change. The beach, from the angle of the 

 island near Siasconset, has gradually been extending northward so 

 that for some years the base of the cliff has been protected from 

 the erosive action of the waves. As a result of this protection, a 

 large part of the surface of the cliff has now become clothed with 

 vegetation. This covering is mainly of the coarse grass which so 

 readily obtains a foothold when actual erosion is prevented. This 

 change of the contour of the beaches has for years been given 

 much attention. In this particular case its practical side is seen, 

 for if active erosion should continue the lighthouse might become 

 endangered. This protection makes harder the work of excavation 

 and necessitates removing a large amount of loose material in 

 order to reach portions which are in their original condition. 



From comparisons made during the past summer the section 

 at present conforms most nearly to that given by Merrill in 1896, 

 although in the fossiliferous beds a difference in thickness was 

 noted. It is probable that these beds are of varying thickness in 

 their different parts. The following section is given by Merrill at 

 a point about three hundred yards south of the lighthouse, where 

 the last summer's work was done : 



