234 CARBONIFEROUIS FORMATIOKS AND FAUNAS OF COLORADO. 



C-olorado. However, possibly the siinio species oecur in the unidentifiable forms 

 preserved as int<Mniil casts in chert, which I have cited simply as minute gastropods 

 in the lists from the Leadvillc, San Juan, and Crested Butte areas. These shells are 

 all of extremely small dimensions, a circumstance which, taken with their not very 

 perfect preservation, has made their specific identification difiicult and uncertain. 



Into tills geographic division also probably fall four collections made near the 

 junction of the Grand and Eagle rivers. Station 21'.ti> is on Grand River, 1 mile 

 below Eagle River. Here was obtained only ('unidarid crittafiihi. ?. I can find no 

 reference to this collection in published reports, and its hoi'izon is not known. 

 Probably this material was collected by Marvine, whose report upon the Grand 

 River region, owing to his death, was never published. 



From station 2192 we have only Pleurophorus angulatus ?. This locality, which 

 could not have been far from station 2190, is described on pages 242 and 243 of the 

 Hayden annual repoi't for 1873," and the fossils were collected from bed No. 12 of 

 the section. The horizon seems to be near the top of the Weber shales, or just at the 

 base of the Maroon formation. The other fossils mentioned besides the Pleurophorus 

 have not come to hand. 



Of station 2325 all that is known is that it is located on Grand River in north- 

 western Colorado. The description of station 2324 is still less exact, the label read- 

 ing "Ranch west of Camp 59." The latter collection appears to have been made by 

 Marvine, and the fossils probably were not included in any published report. 



From station 2324 we have Ohtmetes mesolobns, Ohonetes flemingl., Marginifera 

 haydenen^is, Marginifera maricata, Spirifei' cam,era,his, and Scminula si(Milita. 

 From station 2825 appears onl^' Marginifera haydenensis. The latter species is not 

 found elsewhere in Colorado, save only at station 2324, and the preservation is so 

 exactly alike in the two lots as to arouse the suspicion that they are really parts of 

 the same original collection. In point of j)reservation these fossils, which are 

 weathered free and more or less covered with a reddish coating, are diflerent from 

 any of our Colorado material, and I suspect that the labels may be wrong, and that 

 they may not have come from Colorado at all. 



Reall}^ the scanty collections from stations 2288 and 2289, together with the few 

 collections made in connection with the stratigraphic work of the Leadville mono- 

 graph and the Tenmile folio, should be considered here; but 1 find it more advanta- 

 geous to include them in the discussion of the Leadville fossils. From station 

 2288 we have only Spirifer rochyinontanus, and from station 2289 onlj' Sjnrifer 

 rocky montanu>< and Spirifer })oonensis f. With this scantj' and unsatisfactory 

 collection the paleontologic evidence from the Grand River region concludes. 



aU. S. Geol. Geog. Surv. Terr., [Seventh] Ann. Kept., for 1873, 1874. 



