470 GEOLOGICAL SURVEY OF THE TERRITORIES. 



26. Sjyirifer Uneatus, Martiu, (spe- 



cies.) 



27. Snirifer Like some forms of S. increhescens, 



Hall. 



28. Spirlfer triradialis, Phillips ('?)* 



29. Spii'iferiiia octopUcata, Sow- 



erb^' May be the same as S. EentucJicnsis, 



Shum. 



30. Fcfzia vera, Hall (?) 



31. Tcrehratula arcuata, Swallow {'^:). Almost certainly the same as T. 



hovidens, Morton. 



32. TercbraUila A small species possibly identical 



with T. turgida, Hall. 



33. Astartella Newherriji, Meek (?) ..I can see no difterence in the sin^jle 



specimen examined, from the Ohio 

 species. 



34. Cypricardina , Has the external appearance of the 



genus. 



35. Plaiyceras. 



36. Plenrotomaria spluvntlata, Con- 



rad The specimen agrees well with de- 



l)ressed varieties of Mr. Conrad's 

 species from the western coal- 

 measures. 



37. Enomplialus Fragments of cast of a large species. 



38. Ph ilUpsia Fragments. 



DIVIDE BETWEEN ROSS FORK AND LINCOLN VALLEY, MONTANA. 



Names. Remarks. 



1. Zaplircntis ^Sfcmshitryi, Hall (!) ■ 



2. Ci/alhophyUum subewspitosumj 



' Meek.t 



3. Lophophylhim ov Cyatliaxonia. . .Vevlxix^^ move than one small spe- 



cies. 



4. Syringopora. 



5. Platyeriiius Body only, of a very small globose 



species. 



6. Pentremites Bradleyi, Meek.f 



7. Pentremites Godoni, Hefrance ('?) 



8. Pentremites conoidens, Hail. 



* A very abuudaut, gregarious little shell, closely resembliug S. triradialis, vox. sexra- 

 dialis, as illustrated by Mr. Davidsou, excei>tiug tliat the largest of hundreds of speci- 

 iiwms are less thau oue-fourth the size of well-developed individuals of that form. It 

 also ditiers in being constantly wider than long, instead of the reverse, and in having 

 the beak of its ventral valve always proportionally shorter ; while it shows a faint 

 sulcus aloug the mesial fold toward the front, and a corresponding very slight ridge in 

 tlie bottom of the sinus of the other valve. I think it probably a new species. If so, 

 it may bo called S. agdaius. 



1 1 ]iave figured and described this species in Mr. King's unpublished report. Its 

 corallites are long, cylindrical, more or less llexuous, and loosely branching instead of 

 growing in compact, fasciculated, orasterform masses, as in C.cwsjjitoniini, Goldfuss. Ic 

 has a more developed, more transversely wrinkled, and less striated eintheca (when 

 not worn) thau Goldfuss's species. 



t A small species like P. Ko7unckiams, Hall, but shorter below, and having its psetid- 

 anibulacra more deeply excavated aloug the middle, with their pore pieces more 

 trausverse. ■ 



