MARYLAND GEOLOGICAL SURVEY 135 



Fossils are rare in the lower two-thirds of the Caryocystites bed, but 

 a fauna of over 50 species has been collected from the upper third, particu- 

 larly from the upper 8 or 10 feet. As it is unlikely that this bed will 

 ever be found exposed in Maryland, it was thought sufficient for present 

 purposes to describe and illustrate only enough of its species to show its 

 general faunal character. It contains such typical Chazyan brachiopods 

 as Camarotoechia plena (Hall) and Hebertella vulgaris Raymond, with 

 species of other classes indicating a similar early age in association with 

 a few bryozoans and other fossils that have been found elsewhere only in 

 Black River deposits. The determination of the age of the bed would 

 therefore seem to be uncertain, but as it occupies the position between the 

 earliest Black River (Lowville) formation and the latest Stones River 

 division which elsewhere is filled by Upper Chazyan deposits with similar 

 faunas, it is believed advisable to refer the Caryocystites bed to the 

 Chazyan. On the other hand, since the main part of the fauna is de- 

 veloped only in the upper beds, it is possible that the entire division is of 

 Chazyan age and that the upper part contains an earlier appearance of 

 species commonly found elsewhere in the Black River. The fauna from 

 this bed, as identified by Ulrich, is listed below. This faunal list, as well 

 as others of the Chambersburg limestone which follow, is introduced only 

 to give a general idea of the life characteristics of the various beds. Com- 

 plete lists of each division can only be published when a monographic, 

 study of the Chambersburg faunas has been finished, a work which is far 

 beyond the scope of the present volume. To give some idea of this fauna 

 the specifically determined forms of the following list are described in this 

 volume. 



Fauna of the Caryocystites Bed, Chambersburg Limestone 



Solenopora compacta (Billings) 

 Columnaria halli Nicholson 

 Tetradium columnar ~e (Hall) 

 Carabocrinus sp. (plates) 

 Caryocystites sp. (plates) 

 Anolotichia sp. 

 Nicholsonella cf. 2V. laminata 

 Batostoma cfr. B. magnoporum 



