26 Fossils from the Lower Coal Measures — Keyes. 
MOLLUSCA. (20-34). Pleurotomaria graysvillensis N. and p. 
T „ „ , , . , ,rr r>v carbonaria N aiul P. 
Lamelhbranchmta. (7-9). (nov sp ) 
Myalina swallovi McC. Anomphalus rotulus M and W. 
Aviculopecten cotanus M. and W. Kuoniphalus ruposus Hall. 
negleftus Geinitz. r— pernodosus M and W. 
Nuculana bellistriata Stevens. Bellerophon carbonanus Cox. 
Nucula parva McC. monfortianus N. and P. 
ventricosa Hall. percarniatus Conrad. 
Schizodns (sp. nnd.) Cephalopoda.. (2-5). 
Clinosphitha radiata Hall. n,.tv.„,i.^^.>t, ..„ .K„„„io nf r- 
c^i^r,<^..,,To c.^i...,it^...^;» n^^ Orthoceras nishensis McC. 
Solenomya soleniformis Cox. 
(sp. inid). 
Gasteropoda. (10-20). Nautilus occidentalis Swallow. 
■ ^ lasallensis M and W. 
Dentalmm annulostriatum M. and W, winslovi M and W. 
meekanum Gein. 
Act;eonia minuta Stevens. Crustacea. (2-2). 
Orthonema conica M and W. Cythere nebracensis (?) Geinitz 
Streptaeis whitheldi Meek. Phyllipsia (sp. und.). 
Aclisina mniuta Stevens. j t- \ t- i 
robusta Stevens. Vertebrata (2-2) 
Macrocheilus newberryi Stevens. 
gracilu.s Cox. Pisces. 
(nov. sp.) Petrodus occidentalis? 
Pleurotomaria brazoensis Shumard. Dlplodus (sp?). 
Summing up the predominant faunal features as presented ini 
the accompanying synoptical table, it appears ( i ) that in those 
groups having an optimum habitat marine there was not only 
a fewness of species but also an extreme paucity of individuals; 
(2) that brachiopods, though well represented in both genera 
and species, were not as proportionately abundant as might be 
expected when it is remembered that this type of life had now 
reached. its culmination and greatest expansion, and (3) that the 
fauna was predominantly molluscan. 
The coelenterates, bryozoans, and echlnoderms form indeed a 
very inconsjDicuous proportion of this local fauna, only three 
or four specifically distinguishable traces of each grouj^ beings 
obtained. Though the brachiopods are represented by fourteen 
species included in nine genera they are with three exceptions 
of comparatively rare occurrence ; Productiis 7Jiuricatus^ Chon- 
etes mcsoloba and Discina nitida only being abundant. The 
brachiopods are, however, all depauperate, attesting conditions, 
at the time they lived, extremely unfavorable to their full 
development, and to the attainment of a normal size that under 
more congenial circumstances would have been rendered pos- 
sible. Molluscan life, while the black shales forming the roof 
of coal No. 3 were being laid down, flourished luxuriantly,, 
especially the gasteropods which in number of species comprise 
more than one-third of the entire fauna. Not only did the gas- 
teropods exceed in species but they far out-numbered all others- 
ndividuals, while as a rule they were small in size, and some 
