832 



NORTH AMERICAN INDEX FOSSILS. 



Fairview formation — lower Cambric of 



Canadian Rockies. 

 Falcate — curved like a scythe or sickle. 

 Falciform — sickle-shaped. 

 Fascicle — a small cluster. 

 Fasciculate — clustered, grouped in bun- 

 dles. 

 Fasciole — in echinoids, a narrow band 



of close granular ornamentation (see 



II., 575, and Fig. 191 0- 



Anal fasciole — the fasciole surround- 

 ing the anus. 



Lateral fasciole — see Fig. 191 1. 



Peripetalous fasciole — see Fig. 191 1. 



Subanal fasciole — the fasciole enclos- 

 ing a space beneath the anus. 

 Fathom — a measure of length equalling 



six feet, used chiefly for depths of 



the sea. 

 Fauna — all the animals living in an 



area or epoch. 

 Fayetteville shale — lower division of 



Boston group, Arkansas. 

 Femur — in insects the middle segment 



of the leg (see IL, 420). 

 Fenestrules — the openings between the 



branches of a bryozoan colony. 

 Fernando beds — lower Pliocenic of 



California. 

 Fern Glen limestone — Kinderhook of 



Missouri. 

 Fiber — any fine, slender, thread-like 



substance. 

 Fibrous — consisting of fibers. 

 Filament — a fine thread or fiber. 

 Filiform — thread-shaped, very slender. 

 Fimbrice — fringes. 

 Fission — the act of splitting or dividing 



into parts. 

 Fixed cheek — that part of the cephalon 



of a trilobite which lies between the 



glabella and the facial suture (see 



Figs. 1542, 1557). 

 Flabellate — fan-shaped. 

 Flagellum (plural flagella) — a long, 



lash-like appendage (see II., 387, and 



Fig. 1692). 

 Flange — a projecting rim. 

 Flathead quartzite — middle Cambric of 



Yellowstone region. 



Flat Rock dolomite — upper Monroan of 

 Michigan, Ohio, etc. 



Flexuous — bent in a winding or zigzag 

 manner. 



Flora — the vegetation of an area or 

 epoch, 



Florissant beds — continental Oligocenic 

 of Colorado. 



Floscelle— in some echinoids, the petal- 

 like expansion of the ambulacral 

 plates near the mouth opening, ac- 

 companied by an enlargement and 

 crowding of the pores (see Fig. 1930). 



Floyd shale — upper Mississippic of the 

 southern Appalachians. 



Fold — an elongate elevation. 

 Medial fold — see median fold. 

 Median fold — in some brachiopods, 

 the central and usually the largest 

 elevation extending from the beak 

 to the front of the shell ; it is 

 usually upon the brachial valve. 

 Mesial fold — see median fold. 



Foliate — leaf-like ; in the form of a 

 thin, leaf-like expansion. 



Food grooves — in crinoids, etc., the 

 grooves in the ambulacra through 

 which the food is urged into the 

 mouth. 



Foramen — an opening or pore ; specific- 

 ally, in brachiopods, the opening for 

 the pedicle in the pedicle valve. 



Foramina — plural of foramen (see I., 

 8). 



Fort Payne formation — lower-middle 

 Mississippic of southern Appalach- 

 ians. 



Fort Scott limestone — lower Coal Meas- 

 ure limestone (middle Carbonic) of 

 Kansas. 



Fort Union formation — lower Eocenic 

 of Montana (continental). 



Fort Worth limestone — upper Coman- 

 chic (Washitan) of Texas. 



Fossil — the remains of an organism or 

 anything indicating the presence of 

 an organism, buried by natural causes 

 and preserved in the rocks of the 

 earth's crust. 

 Classification of — see I.. 6. 



