254 BULLETIN: MUSEUM OF COMPARATIVE ZOÖLOGY. 
of the series, such as the phenomena observed at Squantum, Huit’s 
Cove in Hingham, Attleboro, and Purgatory, indicate that lacustrine 
action was not alone responsible for the deposition of the Carbonifer- 
ous series but that powerful agents of transportation were at work 
supplying and perhaps depositing some of the detritus. 
Estuarine. The idea of estuarine origin was held by Crosby in con- 
nection with his earlier views of the marine origin of the conglomerate 
(b, p. 252). Other writers have described the early condition of the 
region as a “broad erosion trough” or an “arm of the sea” (Shaler et 
al., p. 9; LaForge, p. 90), expressions which might be interpreted as 
implying estuarine origin. In the comparisons on page 249 it was 
shown that while there were a number of points of resemblance be- 
tween the characteristics of the sediments of the several basins and the 
features that may be expected in estuarine strata, yet the agreement 
in texture and in features of bedding was not so close as in the case of 
some of the other types. Moreover, the absence of any definite 
traces of marine life and of brackish water forms, unless some of the 
plant remains can be so considered, is opposed to the idea of estuarine 
conditions. The red colors, ripple-marks, mud-cracks and organic 
impressions that have been observed at various localities are not so 
frequent as might be expected in strata of estuarine origin; and they 
are not distinctive, since such features may be expected to occur in 
fluviatile sediments. 
Fluviatile. The fluviatile origin of some of the sediments of the 
Narragansett Basin has been, advocated by Shaler and. Woodworth 
(Shaler et al., p. 53, 67, 176). From the comparisons on pages 249 
and 250 it will be seen that the characteristics of the sediments under 
discussion agree perhaps more closely with the features of fluviatile 
deposits than with those of any other type, although even here the 
correspondence is not complete. The bedding is on the whole more 
regular than might be expected in fluviatile strata and the arrange- 
ment of lenses, so far as observed, does not appear to agree with the 
idea of linear bundles.. Nevertheless, it has been shown that fluvia- 
tile deposits present a wide range in texture and bedding, from high | 
irregularity to almost complete regularity. Thus the prevalence 
of banding and fairly uniform bedding need not preclude the idea of 
fluviatile origin. The evidences of fresh-water deposition already 
mentioned are favorable to this view and the occurrence of the coarsest 
conglomerate at the top of the Narragansett series, previously advanced 
in support of the non-marine character of the sediments, is also favor- 
able; for Oldham has pointed out (see page 112) that in the fluviatile 
