Fossil Shells in the Drumlins of the Boston Basin. 489 



crispata, Siliqiia squama (?), Malinia lateralis, Saxioava 

 norwegica (?), Cyprina islandica, Callista convexa, Anomia 

 glabra, Pecten magellanicus, Astrangia dance. 



In this Journal for March, L894, Mr. Uphatn calls attention 

 to the previously unpublished observations of Mr. Warren W. 

 Herman, a zealous collector, who had found at Great Head 

 the four new species subsequently published by Mr. Dodge, 

 and one other — Orepidula plana. Mr. Herman, who has 

 kindly placed his results at our disposal, has examined care- 

 fully only three sections — Great Head, Grover's Cliff and 

 Telegraph Hill. He has found in all thirty-five species, eight 

 of which have not been found by any other observers ; viz : 

 Neptunea ventricosa, Sipho stimpsoni, Astyris lunata, Beta 

 (sp.), Utriculus Ganaliculatus, Petricola pholadiformis, Ma- 

 coma fragilis, and Argina pexata. This brings the number 

 of the drift species up to fifty-five. 



The accompanying map shows the distribution of all the 

 known fossiliferous sections, including the wells noted by early 

 writers in Jamaica Plain, East Boston, and on George's Island, 

 and two other wells to which our attention has been called, 

 one in Braintree and the other in Cohasset. The map is 

 intended especially to show the relations of the fossiliferous 

 sections to the outlines of Boston Harbor ; and it is apparent 

 at a glance that the facts support the views of Lewis and 

 Upham. If the shells are preglacial inhabitants of the Boston 

 Basin which were scraped up by the ice-sheet and incorporated 

 with the normal drift, they ought to be found, as they are, 

 chiefly in the central and southern portions of the basin, and 

 overlapping its southern but not its northern margin. The 

 non-occurrence of shells in the numerous drumlin sections 

 along the southern shore of the harbor is readily explained by 

 the fact that the sections are all too shallow. In fact, it may 

 be said that fossil shells are found at every point where recent 

 erosion has cut through the buff till into the unoxidized or 

 blue till, say to a depth of thirty feet or more. That the 

 shells do actually exist in these seemingly barren drumlins, 

 and others still farther south, is proved by the wells just 

 referred to. The facts are as follows : Fragments of the 

 round clam ( Venus mercenaria) were found by Mr. Titus 

 Burbank some years ago in digging a well near the summit of 

 James Hill (a typical drumlin), northeast of Scituate Pond in 

 Cohasset. The well is 45 feet deep; and the shells were 

 observed only near the bottom.* Seven years ago Mr. Charles 

 H. distance of Braintree dug a well at the house of Ibrahim 

 Morrison on a flat irregular drumlin between Braintree and 

 East Braintree ; total depth 49 feet — 29 feet in " gravel and 



* Occasional Papers, Boston Soc. Nat. Hist., vol. iv, p. 143. 



