NIAGARA FALLS AND VICINITY IO3 



Lower shales. The beds immediately succeeding the Clinton lime- 

 stone are calcareous shales with frequent thin limestone layers. The 

 latter are the most fossiliferous, being in general entirely made up 

 of organic remains. The calcareous beds of the lower 5 or 10 feet 

 are particularly rich in crinoid remains. Chief among these or- 

 ganisms, on account of its abundance and perfection, is the little 

 triangular Stephanocrinus or 11 at us, which may be 

 found in most of the calcareous layers. Fragments of Eucalyp- 

 tocrinus are always common, while the characteristic Niagara 

 cystoid Caryocrinus or n at us is also found, though not so 

 abundantly as in the upper part of the lower division. The most 

 abundant brachiopod of the lower shales is Whitfieldella 

 nitida oblata, similar to the specimens found in the lime- 

 stone lenses. The little Orthis, D a 1 m a 11 e 1 1 a e 1 e g a n t u 1 a , 

 is also common, ranging throughout the lower division of the shales. 

 Spirifer niagarensis is common above the lowest 3 or 4 

 feet of the shale. Orthothetes subplanus, a large, sub- 

 semicircular and nearly flat brachiopod, is abundant in some of the 

 calcareous layers, which at times seem to be composed of it, so 

 thickly are these shells piled one on the other. A t r y p a nodo- 

 striata is the commonest representative of the genus, the larger 

 A. reticularis, so abundant in the upper Clinton, being com- 

 paratively rare and subordinate in development. In the limestone 

 bands A. nodostriata is usually rotund, but in the shaly beds 

 it is most commonly compressed. Trilobites are comparatively rare 

 in these lower shales, though representatives of all the species found 

 in this region have been obtained from them. Bivalve molluscan 

 shells are also uncommon, but the gastropods, D i a p h o r - 

 ostoma niagarense and Platyceras are not infre- 

 quent. 



Some of the calcareous bands are almost barren of organic re- 

 mains, but in most cases these beds will be found to constitute the 

 chief repositories of the fossils. 



Bryozoa beds. A short distance south of the third watchman's 

 hut, the section comes to an end, being for some distance replaced 

 by a soil-covered and more or less wooded bank. Where the section 



