CLARK: NEW BLASTOIDS AND BRACHIOPODS. 369 



This species was originally described by Meek in 1873 in a footnote. 

 His (lescriptioii follows. "A small species like P. konitickianus, Hall, 

 hut shorter below, and having its pseudambulacra more deeply exca- 

 vated along the middle, with their pore pieces transverse." It 

 remained for Hambach, in 1903, to supplement this meager and alto- 

 gether insufficient description by the following words: — " Body small, 

 obtuse, conical. Basal portion almost flat, and resembling that of 

 Pentremitcs conoideus very much, but being more rounded and having 

 a larger articulation surface for the column, in proportion to its size, 

 than Pentremitcs conoideus. Ambulacra broad, excavated along the 

 middle, and having rather narrow integumental plications, there 

 being about twelve to one eighth of an inch. Deltoids visible exter- 

 nally. Genital openings as in all true Pentremitcs. 



" This species was first described by Meek, but merely in a footnote, 

 comparing it with Pentremitcs koninckianus = conoideus Hall. It 

 differs from Pcntrcmites conoideus in being more obtuse, with broader 

 and more deeply excavated ambulacra than Pentremites conoideus in 

 which the ambulacra are narrow, more rounded, and the surface pli- 

 cations coarser. The interambulacra are depressed more in Pen- 

 tremitcs conoideus than in this species. It differs from Pentremites 

 godoni in being not as round, with more depressed ambulacra, and in 

 not having the sharp crest-like margin around the sinus. 



"Geological formation and locality. Subcarboniferous on the 

 divide between Ross Fork and . Lincoln Valley, Montana. First 

 mentioned in F. V. Hayden's Sixth Annual Report of the United 

 States Geological Survey of the Territories, 1873, p. 470. Types in 

 the Smithsonian Collection, numbered 24,529." 



Pentremites conoideus Hall. 



Pentremites conoideus Hall. Meek, Rept. U. S. geol. surv. Montana, Idaho, 

 Wyoming, and Utah, 187.3, p. 470. 



This species was listed by Meek in 1873 among fossils collected in 

 Carboniferous strata from the divide between Ross Fork and Lincoln 

 Valley, ^Montana. 



In 190.5, Mr. Earl Douglass found a specimen which was identified 

 by Dr. P. E. Raymond as Pentremites conoideus, in a decomposed lime- 

 stone on Old Baldy. From the same stratum a large number of other 

 fossils were obtained, all of them species characteristic of the Madison 



