THE SANDSTONE OF FOSSIL RIDGE 187 
Fragments of undetermined fossil wood are common south of Ft. Collins, often 
honeycombed by Teredo or other wood-boring mollusks. There are also casts of perfectly 
round, smooth, straight plant stems, undetermined. 
ANIMALS 
CCELENTERATA 
Beaumontia solitaria White 
Fossil Ridge is the type locality for this species. We have not seen it and find no 
other record except a conglomerate pebble in the Denver Beds. 
Chetetes dimissus White 
The type locality is Fossil Ridge, where it is abundant. Not recorded elsewhere, 
but we found it common also at the same horizon at Rocky Ridge, north of Ft. Collins. 
ANNELIDA 
Serpula n. sp. 
Common at Fossil Ridge, the type locality, and at Rocky Ridge. Have not seen it 
elsewhere. An undetermined Serpula reported from the lower Pierre of the Denver Basin 
may be of this species, but we have not seen specimens of it. 
POLYZOA 
Membranipora sp. 
An undetermined species found on fragments of Anchura and Placenticeras at Fossil 
Ridge, in the latter case in such position as to show growth after the cephalopod had 
been broken up. We found the same or a similar species on Baculites below the Hygiene 
sandstone at the mouth of Little Thompson canyon, northeast of Lyons. 
MOLLUSCA 
PELECYPODA 
Panopea berthoudi White 
Described as Glycimeris berthoudi by Dr. White, but belonging to the genus Panopea, 
following Dr. Dall’s able treatment of that and related genera, which appears to be gener- 
ally accepted. The type locality of this species is Fossil Ridge. We are aware of no 
other records, but have received several specimens collected near Meeker, Colorado, by 
Professor F. H. Hopkins. 
Pinna lakesi White 
The type locality is Fossil Ridge, where it is quite common. We know of no other 
records except one in Canada [J. F. Whiteaves, Contributions to Canadian Paleontology, 
Vol. I, Pt. I, p. 84, 1885, “Geol. and Nat. Hist. of Canada’’], but have seen one other 
specimen collected near Meeker, in northwestern Colorado, by Professor F. H. Hopkins. 
Inoceramus crippsii var. barabini Morton 
Numbers of specimens are found at Fossil Ridge. In Boulder District and at Love- 
land and Berthoud it is found in, below and above the Hygiene sandstone. In the Denver 
Basin monograph the species is credited to the Fox Hills and upper and middle Pierre, 
but from Boulder to five miles north of Ft. Collins we have found it in the lower third of 
the Pierre and have seen no examples in Fox Hills strata. In the upper Missouri region 
it is found in Pierre strata (Meek). 
