Pinus Aristata Research Articles

An Ancient Foxtail Pine

MY young friend Mr. Allan Caplan has recently obtained a remarkable series of fossil plants in the Miocene shales at Creede, Colorado. Among these the conifers are especially interesting, and one specimen consists of a small cone, about 19 mm. long, broadly oval in form, the scales armed with long prickles (Fig. 1). I sought the advice of my colleague, Dr. Edna L. Johnson, who at once produced some immature cones of Pinus aristata, Engelmann, the foxtail pine of the western mountains of the United States. On comparison, it was impossible to see any difference. Knowlton (1923) described a Pinus crossii from Creede, based on foliage which does not appear to differ from that of P. aristata.

Studies in Transpiration of Coniferous Tree Seedlings

Adequate studies of transpiration promise to yield much information regarding the water relations of trees. Water consumption in relation to growth, capacity for adjustment in time of water shortage, and ability to obtain moisture from the soil are important questions on which a knowledge of transpiration may be expected to shed light. In i9i9 and I920, transpiration measurements were made at the Southwestern Experiment Station on seedlings of four conifers native to the mountains of Arizona and New Mexico. These species are western yellow pine Pinus scopulorum, Douglas fir Pseudotsuga taxifolia, bristlecone pine Pinus aristata and Engelmann spruce 2' Piceca engelmanni. The vertical arrangement of their natural habitats, beginning with the lowest, is approximately in the order above given. In the zone of yellow pine which ranges between altitudes of 7,0oo and 8,500 feet, the annual precipitation is around 22 inches, and the mean maximum temperature for the growing season is about 75 degrees. Precipitation increases to about 30 inches, while the mean maximum temperatures for the growing season falls to about 6o degrees in the zone of bristlecone pine and Engelmann spruce.

Scientific Serials

American Journal of Science and Arts, February.—The first article is an obituary notice of Sir W. E. Logan, lead before the Natural History Society of Montreal last October.—Mr. W. B. Taylor contributes a continuation of his history of recent researches in sound.—Mr. A. H. Rowland continues his studies on magnetic distribution, in which he critically examines M. Jamin's recent work.—On the rifts of ice in the rocks near the summit of Mount McClellan, Colorado, and on the different limits of vegetation on adjoining summits in the territory, by Edward L. Berthond. Mount McClellan is 13,430 feet high, and contains mines which are extensively woiked. At a height of 13,100 feet, and about 30 feet from the entrance of the tunnel of one of the mines, were three or four veins of solid ice, parallel with the bedding of the rock, and filling all its inner side with cracks and fissures. In another tunnel 300 feet westward and about 100 feet from the entrance, veins of ice were also met with. It has been suggested that this ice has remained ever since the Glacial period. The mountain presents these two strange antagonistic phenomena in immediate proximity. On one side ol the valley there is a mountain slope facing north-east, well grassed, totally devoid of shrubs and trees, where the rocky débris are underlain by a perpetual icy coat hundreds of feet in depth, supporting on its surface a growth of plants strictly Alpine and Arctic, and abounding with Ptarmigan, Lagopus leucurus, and the tail-less, earless marmot. A list of plants found bloom Oct. 2, 1875, is given. Less than half a mile distant on the opposite slope of the vale Pinus aristata of large size and a profuse growth of birches, willows, grasses, and arbutus abound.—On a new form of lantern galvanometer, by Francis E. Nipher, which possesses the advantages of being adaptable to any vertical lantern; the distance between the deflecting coils is readily varied and can be adjusted to currents of various intensity; the resistance of the galvanometer is quickly varied from one half to twice the resistance of the galvanometer coils.—On the occurrence of tartronic acid, with some remarks on the molecular structure of glyceric acid, by S. P. Sadder. A comparison is made of two views taken of glyceric acid, and It is suggested that there are two isomeric acids, one of which is normal and the other an unsym-metrical acid.—On the “chloride formation” on the western border of the New Haven region, by J. D. Dana.—A new Tertiary lake basin, by G. B. Grinnell and E. S. Dana, During recent explorations a new series of Tertiary deposits has been found at Camp Baker, Montana; they indicate the existence in this region of a Miocene lake basin, which was succeeded by another lake basin in Pliocene time.—The remaining papers are: The product of the action of potassium on ethyl succinate, by Ira Remsen.-The action of ozone on carbon monoxide, by the same.—The appendix contains an article on the Dinocerata, by O. C. Marsh, with five plates.