SNYDER CREEK SHAI.E. 



41 



sionally in contact with it. Its surface was deeply eroded 

 before the earliest Mississippian seas advanced though the 

 relief of the surface of the entire area over which it occurs was 

 not greater than 150 feet. The Sylamore sandstone often fills 

 valleys with sides of Snyder Creek shale and bottom of Callaway 

 limestone or older rock. At the type locality, Sylamore, a few 

 inches to 2 feet thick, is the overlying rock. 



Paleontology. — Fossils are abundant in several members of 

 the Snyder Creek shales but several members are not fossiliferous. 

 The faunules are decidedly different at different localities and 

 in different members at the same locality. Stromatopora solidula 

 Hall and Whitfield seems to occur in only one member about 

 15 to 25 feet from the bottom. Spirifer annae Swallow is present 

 in the same member and not below or above. Lioclema occidens 

 (Hall and Whitfield) is abundant near the bottom and is rare 

 above the middle. Pelecypods are abundant in the upper 15 

 feet. The following is a list of all of the indentifiable fossils 

 from the Snyder Creek that the writer has seen. Greger's 

 list 1 , published in 1909, was preliminary. Several differences 

 between that list and the present resulted from differences in 

 identifications. Greger's species Acervularia profunda Hall, 

 Gypidula comis Owen, and Philhedra crenistriata Hall, the writer 

 has not seen. 



LIST OF SPECIES FROM THE SNYDER CREEK SHALE 



Coelenterata 



Aulopora repens Knorr and Walch (c) 



Ceratopora snyderensis Branson (r) 



Chonophyllum ellipticum Hall and Whit- 

 field (a) 

 Hydrozoa 



Stromatopora solidula Hall and Whit- 

 field (a) 

 Crinoidea 



Dactylocrinus concavus (Rowley) (r) 



Melocrinus gregeri Rowley (r) 



Melocrinus lylii Rowley (r) 



Melocrinus tersus Rowley (r) 

 Bryozoa 



Lioclema occidens (Hall and Whit- 

 field) (a) 



Rhombopora missouriensis Branson (a) 

 Brachiopoda 



Athyris fultonensis (.Swallow) (e) 



A try pa gregeri Rowley (r) 



Airy pa reticularis (Linnaeus) (a) 

 A try pa spinosa Hall (a) 

 Camaroloechia depressa Kindle (r) 

 Camarotoechia gregeri Branson (r) 

 Cranaena calvini (Hall and Whitfield (r) 

 Crania famelica Hall and Whitfield (c) 

 Cyrtina triquetra Hall (c) 

 Orbiculoidea sp. (r) 



Pentamerella missouriensis Branson (r) 

 Productella callawayensis (Swallow) (c) 

 Pugnoides altus (Calvin) (r) 

 Schizophoria striatula (Schlotheim) (a) 

 Schuchertella arctostriata (Hall) (r) 

 Spirifer annae Swallow (c) 

 Spirifer euryteines Owen (a) 

 Stropheodonta boonensis Swallow (a) 

 Stropheodonta callawayensis Swallow (a) 

 Stropheodonta cymbiformis Swallow (a) 

 Stropheodonta demissa (Conrad) (a) 

 Stropheodonta equicostata Swallow (a) 



'Am. Jour. Sci.. vol. 27, pp. 376-377. 



