110 University of Texas Bulletin 



It is evident that the group of Hemiaster elegans of the Fort Worth lime- 

 stone is in an unsatisfactory taxonomic condition and contains more than 

 one species. 



The other individual of Epiaster aguilerae is smaller but similar in 

 proportions to the one figured here. Like it also, the widest point is 

 just anterior to the apical system and the contour is rounded; the form 

 of the test is longer and somewhat more pointed posteriorly. The long- 

 itudinal section is essentially the same. The periproct is situated higher 

 and is perceptibly taller and less rounded, being pointed at both ends. 



HORIZON: Basal Fort Worth limestone. 



LOCALITY : Subdivision 5 of Cerro de Muleros ; Individual 1, one-half 

 mile east of Texas Christian University, Fort Worth, Texas, locality 406. 



Individual 2, one-half mile southeast of Mt. Olivet Cemetery, Fort 

 Worth, Texas, lower 10 feet of Fort Worth limestone. 



EPIASTER SUBOBESUS n. sp. 

 PI. 11, fig. 3 



MEASUREMENTS : Length, 89 mm. ; Width, 78 mm. ; Height, 52 mm. 



HORIZON : Top five feet of Weno formation, marl facies ; Pawpaw 

 formation, marl facies. 



TYPE LOCALITY: 720, top of Weno limestone, one mile southeast 

 of Riovista, Texas. 



DESCRIPTION : Test rotund, elevated, tapering posteriorly to a very 

 narrow tall truncation sloping forwards at the bottom in the top of which 

 the very small periproct is located. Contour same as E. wenoensis except 

 more prolonged posteriorly; form straighter sided, much more elevated 

 than that species, apical system proportionately farther forward. Base 

 nearly flat, slightly raised on the posterior mid-line, but much less than in 

 E. wenoensis, excavated for the peristome. Ambulacra straight, arranged 

 as in E. wenoensis, inter-ambulacral areas notably more elevated. Un- 

 paired ambulacrum with about 60 similar slit-like pore pairs obliquely set. 

 Antero-laterals very long, with 90 or more pore pairs in each zone; all 

 pores equal and similar ; postero-laterals with 80 or more pore pairs, equal 

 similar slits. Peristome medium, transversely oval, 6.5x6.0 mm. ; periproct 

 extremely small, circular, 3.5 mm. diameter, much smaller and situated 

 relatively lower than in E. wenoensis. The description applies to the type 

 individual. This species might be taken as an old individual of E. weno- 

 ensis, but this is precluded by the differences cited above. The species 

 having this characteristic size and form, is common in North Texas. 



