Glossary 



Adiabatic winds. Winds caused by extremely cold and heavy 



air following the contours of icecaps. 

 Areole. A structure composed of special cells on the surface of 



a cactus. 

 Asthenosphere. A layer of rocks below the surface crust of the 



earth; it is made "soft" by heat and pressure. 

 Ai'ifauno. The bird population of any region. 

 Biolopography. Special features of the land surface caused by 



the actions of animals. 

 Bolson. A surface structure forming a flat-bottomed bowl 



without outlet. 

 Butte. An isolated tall hill or small mountain with precipitous 



sides. 

 Cirque. A natural arena or amphitheater; such a structure 



caused by an icefield on a mountain. 

 Climax growth. An area of vegetation that is stabilized in form 



and in botanical make-up. 

 Closed canopy. Any plant growth which forms a continuous 



cover at any elevation. 

 Col. A depression or dip in a mountain chain or ridge. 

 Commensals. Two or more kinds of plants or animals that live 



together and are dependent upon each other. 

 Coquina. A material composed mostly of the shells of mollusks 



held together by limy deposits. 

 Deciduous. Capable of shedding or of being shed, as leaves. 

 Deedees for Didis). Small tornado-like whirligigs of dust. 

 Drumlin. A dome-shaped low hill or hillock of gravel and sand 



deposited by an icecap. 

 Dyke. A wall of lava or other igneous material forced up 



through other rock strata; sometimes left standing free when 



the latter are eroded. 

 Ecology. Literally, the study (logos) of houses (oikoi): thus, the 



groupings of living things and their relations with their 



environment. 

 Erratic. In geology, a piece of rock not indigenous to the place 



where it lies. 

 Esker. A long. low. straight or meandering deposit of gravel. 



etc.. left by a retreating icecap. 

 Fades. In geology, the form (composition) of a stratum of any 



kind in one particular area. In botany, the growth form and 



plant composition of an area. 

 Falces. A pair of curved, pointed appendages under the head 



of a spider or certain other arthropods. 

 Fall-off line (or Fall-out line). A term applied to the edge of an 



escarpment or other continuous sudden drop in elevation 



over which many rivers fall. 

 Feral. Wild; applied to an animal, or plant, or even man. 



which has "run away from" domestication. 

 Firn. Snow compacted to a point where its crystals have been 



rearranged in the process of forming ice. 

 Fumarole. A crevice in the earth from which gases or vapors 



issue. 



Gallery forest. A forest that borders a river or lake but docs 

 not extend far back therefrom. 



Geoclimatological. Pertaining to the over-all climate of the 

 whole earth. 



Glabrous. Free from hair or down; smooth-skinned. 



Gravilic creep. Slow movement of objects downhill due to the 

 pull of gravity. 



Interstadial. The pause during which a major ice advance tem- 

 porarily retreats and the climate ameliorates. 



Isostasy. A condition in which the weight upon and the com- 

 pressibility of a stratum are in balance. 



Magma. Molten or plastic layers beneath the earth's crust. 



Massif. A mass of mountains or a mountain range. 



Montane. Typical of, first described from, or descended from 

 mountains. 



Moraine. Debris carried and deposited by a glacier. 



Muskeg. A growth of bushes, sedges, grasses, mosses, and 

 lichens on bogs or swamps in areas of permafrost. 



Ning-ning. Guianese term for the shimmering of air over a 

 highly heated surface. 



Nunatak. The tip of an isolated mountain appearing above an 

 icecap. 



Open canopy. Any plant growth whidi does not form a con- 

 tinuous cover and permits sunlight to reach the ground. 



Palaeocrystic. Pertaining to very ancient ice which has a recog- 

 nizable structure, especially when in frozen earth or in 

 newer ice. 



Parkland. Land covered with isolated trees standing in grass. 



Permafrost. A condition of permanent frost or sub-zero tem- 

 perature; also, ground that is permanently frozen. 



Pliylogeography. The geography of plants. 



Podology. The study of soils. 



Rain forest. A forest that has more than one tier and occurs in 

 an area of very high rainfall. 



Regelation. Refreezing. 



Saprophyte. A plant that grows upon but is not parasitic on 

 another plant. 



Scoria. A form of volcanic exude; also, clay baked by under- 

 ground fires in coal beds. 



Scree. A mass of loose stones or rocks on a mountain slope. 



Solfatara. A spring expelling sulphurous mud. liquid, or gas. 



Stomata. Small pores on the undersides of leaves, through 

 which plants breathe (exude moisture). 



Subdued relief. Uplands that have been rounded by erosion so 

 that no naked rock is visible. 



Succulents. Fleshy-stemmed and/or fleshy-leafed plants that 

 can tolerate high salinity. 



Taiga. The spruce forests of northern Eurasia and North 

 America. 



Tectite. A glassy meteorite. 



Tundra. A type of vegetative growth, mostly of lichens, mosses, 

 and dwarf willows, found in Arctic regions. 



Xerophyle. A plant adapted to surviving extreme lade of 

 moisture. 



Note on the Capitalization of Names of Animals and Plants 



Following an internationally approved rule, the names of species, 

 genera and larger groupings are capitalized. When referring to 

 an individual species, capitals are used: thus the "Red Fox" but. 

 when referred to in general terms, the "foxes." For the dog 

 family. "Canines"; for dogs in general, "dogs." 



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