170 
Transactions Texas Academy of Science. 
Hill, Egbert T. 
(List Given). IV. Age and Significa-nce of the Trinity Division. V. 
Description of Species. Foraminifera : Patellina teccana (Doemer). 
Echinodermata : Epiaster (?) sp. indet. Vermes: Eerpula paluxiensis 
sp. nov. iMolliiscoidea : Genus indeterminate. Mollusoa: Anomia texana 
isp. nov.; Ostrea franldini Ooquand; Ostrea franldini var. ragsdalei var. 
nov.; Pecten stantoni sp. nov.; Modiola hranneri sp. nov.; Leda (?) har- 
veyi sp. nov.; Ciiciillcea gratiota Hill; Guculkea comanchensis sp. nov.; 
Cuciillcea terminalis Conrad; Barhatiw parva-missouriensis Hill; Trigonia 
stolleyi sp. nov.; Trigonia cremt?a/a- [Ro'emer ; Gliione (?) decepta sp. nov.; 
Erlphyla pikensis Hill; Requienia texmia (?) (Toemer) ; Monopleura, 
marcida and M. pinguiscula White; Gorhicida arkansaensis Hill; Gardium 
(?) scrvierense Hill; Proctocardia sp. indet.; Pholadomya knoioltoni sp. 
nov.; Pholadomya Icrchi sp. nov.; Pleuromya (?) lienselli sp. nov.; Isocar- 
dia (?) medialis (Conrad); Natica (?) texana Conrad; Viviparus {Nat- 
icaf) cossatotensis Hill ; Gylindrites (?) sp. indet. ; Biiccinopsis (?) parryi 
Conrad; Tylostonia pedernalis (Roenier) ; Vicarya hranneri sp. nov.; Ncri- 
ncea anstinensis Doemer; Nerithia sp. indet.; N&uinayrki loalcotti Hill; 
Acanthoceras (?) justince sp. nov. Arthopoda: Gypridea texaiva sp. nov. 
fPlantse: Undetermined species. ( “Goniolina ?” of author’s previous writ- 
ings. ) VI plates. 
“lit has heretofore been impossible to present faunal studies of the 
paleontology of the various horizons of the Comanche Series owing to the 
fact that itlie fundamental problems concerning the sequence and relative 
importance of its subdivisions had not been presented until lately, although 
the identity of the series, as a whole, was made known in 1886. Prior to 
that time mosit of its fossils had been described by iShumard, Doemer and 
others, but it was supposed that the species all came from beds which .were 
in some manner equivalents of the upper Cretaceous or the well known 
Aleek and Hayden section. Since the writer ascertained thatt the Comanche 
Series was a distinct and lower Cretaceous formation he has spent several 
years in studying the subdivisions and their extent, in ascertaining the 
stratigraphic position of the fossils or faunas already described, and arriv- 
ing at a rational system of nomenclature. These steps were necessary 
before the homotoxy of the series could be discussed.” Pp. 9-10. 
246. 
Tii'cumcari. 
(Correspondence.) i 
Science, YoL xxii, pp. 23-25. July 14, 1893. 
“The writer first visited this historic locality in 1887, before he had had 
•opportunity to define the Denison beds at the top of his Lower Cretaceous 
section in Northern Texas, and fell into the error, which others have not 
escaped, of concluding, from the peculiar Jurassic-like Gryphaea dilatata, 
Marcou, the only fossils found upon that visit, that the beds were Jurassic, 
and so published his opinion. 
“Later, hoiwever, after having had an opportunity to complete his study 
and arrangement of the stratigraphy of th© Comanche series in Central 
Texas, he discovered in the Denison beds (Denison beds as originally defined 
