Weno and Pawpaw Formations 105 



Weno species until more material is available. Cragin 1 described three 

 species of Holaster, some of which are valid species. Holaster supemus 

 Cragin (Grayson marl, Argyle, Texas), a top-heavy echinoid with a cir- 

 cular apical system, is a Stenonia. The small low species, H. nanus, from 

 the "Vola bed" (Mainstreet?) on the Denison-Bonham road, Choctaw 

 Creek, Grayson County, Texas, is apparently the same low species that is 

 common in the Weno and Pawpaw formations throughout North Texas. 

 The other species, H. completus, which was found in the "Denison beds" 

 and the Mainstreet limestone in Goyson County, has a very distinctive 

 apical system, but has the periproct infra-marginal, and is not a Holaster. 

 In addition, a very small pyritic Holaster whose characters are too im- 

 perfectly known to warrant description, occurs in the basal Pawpaw clay. 



EPIASTER WENOENSIS n. sp. 



PI. 6, fig. 6 



MEASUREMENTS: 



Type: Length 54 mm. 



Breadth 50 mm. 



Height 29 mm. 



Apical system to posterior border 32.5 mm. 



HORIZON : Weno and Pawpaw formations, most abundant in the basal 

 third of the Weno, marl facies, in association with Holaster sp. aff. simplex 

 Shumard, Enallaster bravoensis Bose, E. wenoensis n. sp., Hemiaster cal- 

 vini Clark and H. sp. aff. bexari Clark. 



LOCALITIES: 618, near International and Great Northern Railway 

 track, three miles southeast of Fort Worth, Texas (type locality). 602, 

 611, 612, near Fort Worth, Texas ; near Riovista and Blum, Texas ; three 

 miles north of Gainesville, Texas; Missouri, Kansas and Texas Railway 

 cut one mile north of Union Station, Denison, Texas; and elsewhere gen- 

 erally distributed in the North Texas Weno. Localities 714, 715, 718, 723, 

 and other Pawpaw localities near Fort Worth, Texas, especially in the 

 upper marly portion of the Pawpaw. 



DESCRIPTION : Superficially similar to Hemiaster elegans Shumard, 

 but smaller, smoother, less inflated, less bulged between the ambulacral 

 grooves, and with straighter and narrower ambulacra. The species re- 

 sembles E. aguilerae Bose, but is smaller and differs in the form and am- 

 bulacral details. The Texas Comanchean Epiasters may be distinguished 



'Cragin, Geol. Surv. Texas, 4th Ann. Kept, pp. 165-168. ' 



