NO. 3 CAMBRIAN TRILOBITES 187 



granulations. The resemblance to the cranidium of A. linnarssoni 

 is mentioned in the note on that species. 



Formation and locality.- — Middle Cambrian: (52a) Prospect 

 Mountain formation ; shale interbedded in limestone 500 to 600 feet 

 (152 to 182.8 m.) down northeast slope of Prospect Mountain, 

 Eureka district, Eureka County, Nevada. 



ALOKISTOCARE SUBCORONATUM (Hall and Whitfield) 



Plate 25, fig. 2 



Conocephalites subcoronatus Hall and Whitfield, 1877, Geol. Explor. For- 

 tieth Par., Vol. 4, p. 237, pi. 2, fig. I. (Original description and 

 illustration.) 



Ptychoparia subcoronata (Hall and Whitfield) Walcott, 1886, Bull. U. S. 

 Geol. Survey, No. 30, p. 205, pi. 28, fig. 4. (Reprints original descrip- 

 tion and figure, and comments on species.) 



Ptychoparia subcoronata (Hall and Whitfield) Walcott, 1891, Tenth Ann. 

 Rept., U. S. Geol. Survey, p. 652, pi. 96, fig. 6. (Notes occurrence of 

 species in Low^er Cambrian of New York, and reproduces figures of 

 Hall and Whitfield.) 



There is little to add to the original description of Hall and 

 Whitfield. Additional collections have afforded only the cranidia 

 and shown that the outer surface is roughened slightly by shallow 

 pits and possibly by puncta^. 



The cranidium of A. subcoronatum may be compared with that of 

 A. althea (pi. 25, figs. 3a, 4a), which is most nearly related to it. 



Other species have some strong points of resemblance, such as 

 wide fixed cheeks, boss in front of the glabella, flat, slightly upward- 

 curving frontal rim, and small to medium-sized palpebral lobes. 



The largest cranidium has a length of 8 mm. 



Formation and locality. — Middle Cambrian : Type specimens from 

 Ute limestone, base of Ute Peak, Wasatch Range; (31c, 54 o) Ute 

 formation; ib of section," Blacksmith Fork Canyon, about to miles 

 (16.1 km.) east of Hyrum, Cache County, Utah. 



ALOKISTOCARE TICIDA, new species 



Plate 26, figs. 6, 6a 

 This species is characterized by having a glabella about half as 

 long as the cranidium ; an elongate boss on the frontal limb crossing 

 the frontal furrow ; high and relatively narrow fixed cheeks ; eyes 

 posterior to the center of the cranidium ; rather broad and upward- 

 curving frontal rim, and rather short postero-lateral limbs. The 

 glabella shows traces of three short furrows on each side. 



Smithsonian Misc. Coll., Vol. 53, 1908. p. 196. 



