SEEDLING GROWTH AND SURVIVAL OF RED AND WHITE FIR IN A SIERRA NEVADA ECOTONE

We hypothesized that differential seedling establishment was responsible for the transition from white fir- to red fir-dominated forest. Nearly 2,000 seeds of each species were sown within six fenced gardens that spanned the ecotone (1,902–2,073 m). Germination and seedling mortality were monitored through the first growing season. Red fir germination percentage exceeded that of white fir in all gardens in sites dominated by red fir saplings and overstory trees, and a similar pattern was true for white fir. Survival at the end of the first growing season was low and statistically similar for both species, as was the average length of life for seedlings and the causes of mortality. Relative demographic performances (an integrated measure of germination and survivorship over time) suggest that: 1) open/xeric microhabitats within the ecotone favor white fir over red fir; 2) both open/mesic and shaded/xeric microhabitats favor red fir over white fir; and 3) shaded/mesic microhabitats are equally favorable for both species. Seedlings of red and white fir were grown for 6 mo in a growth chamber that imitated early summer temperature and soil moisture conditions. Red fir seedlings were consistently heavier than white fir seedlings, in part a result of the 2.5 × greater caloric content of red fir seed. Relative growth rates were similar for both. Allocation of photosynthate to roots was greater for red fir than white fir, a result contrary to the expected pattern, given that white fir occurs at more xeric, lower elevations than red fir. No consistent differences between the species occurred in root growth or morphology.     

THE DISTRIBUTION OF COCCIDIOIDOMYCOSIS IN SOUTHERN CALIFORNIA

In coccidioidin skin test surveys among persons of high school age in Saugus, Canoga Park, Banning and Palm Springs areas the average incidence of positive reaction was 15 per cent. Although considerably less than the 68 per cent incidence reported among high school students of Kern County, it is high enough to indicate pockets of relatively high endemicity in Southern California below the San Joaquin Valley.Histoplasmin tests were performed on most of the persons tested with coccidioidin in this survey. The over-all incidence of positive reaction in the group was 7.6 per cent. Most of the subjects with positive reaction to histoplasmin gave a history of having previously lived in some area in the central United States where histoplasmosis is known to be endemic.A few subjects who had positive reaction to coccidioidin tests and who had lived in areas known to be endemic for coccidioidomycosis but not for histoplasmosis, also had positive reaction to histoplasmin. However, the induration produced was always smaller than that caused by the coccidioidin reaction, and there was minimal confusion in interpreting the tests.     

THE USE OF THE MALE CALIFORNIA TOAD IN THE DIAGNOSIS OF PREGNANCY

The California male toad, readily available in most areas of the state, and for many other reasons a better subject for test purposes than the frog, was used in 237 tests to determine the presence or absence of pregnancy in humans. Human urine was injected into the toads, and the cloacal discharge then was examined for the presence of sperm. There were only two false reactions in the series—both false negative. In subsequent tests in both these cases, the result was positive.     

THE NUMBER AND DISTRIBUTION OF PHYSICIANS IN CALIFORNIA

The ratio of physicians to general population in California has been approximately the same for many years, the influx of physicians having kept pace with the population trend.For many years California has licensed more physicians than any other state.The five medical schools in this state have been increasing the number of candidates admitted to the freshman class. Attempts are being made to increase the number of medical schools in this state to seven in anticipation of the future growth and medical needs of the population.The heaviest concentration of physicians is as always in the thickly populated areas as determined by the population physician ratio.A study of the detailed statistics presented in this paper should be of interest to all California physicians.     

STUDIES ON THE CHLOROPHYLLS AND PHOTOSYNTHESIS OF THERMAL ALGAE FROM YELLOWSTONE NATIONAL PARK,CALIFORNIA, AND NEVADA

1. Myxophyceae normally growing at 65°C. evolved oxygen upon irradiation and showed evidence of retaining the power to carry on the process of photosynthesis at 20°C. This indicates that extra thermal energy is not essential for photosynthesis at least over a short period of time. 2. Chlorophyll a and b found in several species of Myxophyceae growing in waters ranging in temperature from 37–72°C. are essentially the same as found in plants growing all over the world. Certain standard chemical tests and spectroscopic examination of the chlorophylls were used as the criteria for these comparisons. The ratio of chlorophyll a to b often varied considerably but in general chlorophyll a showed an increase over the percentage found in most plants. 3. Green algae (Chlorella sp.?) were the only forms found at The Geysers, California. The temperature of the waters from which collections were made varied from 49–66°C. 4. Collections from Beowawe, Nevada were from waters ranging from 60–71°C. The algae belonged to the Myxophyceae and the species were like some of those found in Yellowstone National Park. 5. In some of the calcareous regions of Yellowstone National Park spectroscopic study of the chlorophylls revealed an unidentified absorption band at 548 mµ.