PRINCIPAL GROUPS OF PLAXTS. 117 



Economic Uses of the Coniferae. — Froni an economic point 

 of view the Coniferae are by far the most important group of 

 plants thus far considered. In fact, they may be ranked first in the 

 production of valuable timber. Of those yielding timber the 

 following species may be mentioned : White pine (Pinus Strobus) ; 

 long-leaved, yellow, or Georgia pine (Pinus palusiris Mill) ; 

 spruce pine (Pinus echinata) ; the Redwood of Upper California 

 (Sequoia sempervirens) ; pitch pine of New Mexico (Pinus pon- 

 der osa) ; the Scotch fir, the common pine of Europe (Pinus sylves- 

 tris). Some of the woods are adapted for special purposes: as 

 that of Pinus Celuhra of the high mountains of Europe and 

 'Northern Siberia, which is excellent for wood-carving; red cedar 

 (Juniperus virginiana) (Fig. 75) used in the making of cigar 

 boxes and lead pencils; balsam fir (Abies balsamea) used in the 

 manufacture of wood pulp. 



By reason of the oleoresinous constituents the woods of some 

 of the Coniferae are among the most durable known. A few 

 years ago Jeffrey examined a specimen of Sequoia P enhallozvii 

 which was obtained from auriferous gravels of the Miocene in 

 the Sierra Nevada Mountains and found it to be in a very perfect 

 state of preservation. Penhallow (loc. cit.) considers this to be 

 the most ancient record of an uninfiltrated and unaltered wood. 

 Coleman, in 1898, found in the Pleistocene clays of the Don 

 Valley a specimen of red cedar (Juniperus virginiana) which not 

 only possessed all of the external characteristics of this species 

 but when sawed emitted the aromatic odor of the bark. In the 

 Pleistocene deposits of the western United States and Canada 

 are found more or less unaltered specimens of various species of 

 Juniperus, Pseudotsuga, Picea, and Larix. 



Some of the pines yield edible seeds which have been used 

 by the Indians of Western America ; as the edible or " nut pine " 

 of California and New Mexico (Pinus edulis) ; Pinus monophylla, 

 discovered by Colonel Fremont in Northern California; Pinus 

 Jeffreyi of Northern California; and Pinus Pinea of Europe, the 

 seeds of the latter being used like almonds and known as '' pig- 

 none." The seeds of Pinus Lambertiana (Fig. 72, C) of Califor- 

 nia are baked before being used as a food. This latter species is 

 also known as the sugar pine, as it yields a manna-like product. 



