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1. Although the importance of adequate fat deposits for migrating birds has long been recognized, little is known about causes of intraspecific variation in the size of energy reserves. 2. We studied individual variation in visible fat reserves, body size, state of health and nutrition among autumn migrating Goldcrests Regulus regulus. 3. Birds showing signs of infectious/inflammatory diseases (high red blood cell sedi- mentation rate) or anaemia (low packed red blood cell volume) had significantly smaller fat stores than birds lacking these signs. However, no differences in fat reserves or health state were detected in relation to stage of post-juvenile moult. 4. These results suggest that the ability to deposit fat in the face of an energetically demanding migration may be affected by an individual's state of health.

(1) In coniferous forests in Central Sweden willow, (Parus montanus) and crested tits (P. cristatus) forage in the inner canopy while coal tits (P. ater) and goldcrests (Regulus regulus) forage on the outer, needled tree parts. (2) To test if interspecific competition affects foraging site selection of the two latter species, we reduced the numbers of willow and crested tits by more than half in three 40 ha study plots in the beginning of winter. (3) Later in winter, coal tits and goldcrests increased their foraging in inner canopy in the experimental plots in comparison with three control plots. (4) An experiment is powerful in excluding alternative explanations only if it is based on a sufficient number of repetitions. Observations within a plot may be dependent because they are derived from animals inhabiting the same environment. The simplest way around the problems is to use each plot as a single observation in test. Both coal tits and goldcrests exploited inner tree parts more in all of the three experimental plots than any of the three control plots, which alone is a significant difference. (5) The experiment indicates that interspecific competition affects foraging site selection of sympatric tits and goldcrests, as has been previously suggested by many nonexperimental studies.

The female Goldcrest incubates alone and is not regularly fed by her mate. Incubation starts gradually already during the egg-laying period, and may be fully developed before the clutch is completed. From that time onward the hourly mean egg temperature remains remarkably constant, largely independent of time of day and weather conditions. The overall mean egg temperature, recorded during the continuous incubation period, was 36.54?C. The female regulated the temperature of the eggs by adjusting her attentive time. This is achieved by (1) varying the duration of the periods-off, which is inversely correlated with air temperature, and (2) varying the duration of the periods-on, which is less influenced by the weather conditions, but is significantly correlated with the time of day (light intensity), on average being shortest during the midday hours.

The material described in this paper is part of a collection obtained for the West Texas State College from a quarry in the Lower Pliocene beds of Donley County, Texas. This work was accomplished through the cooperation of the Works Progress Administration in 1936. The material presented is that of a small horse which was obtained from a quarry situated on the Grant property, two miles west of Goldston, and was collected by a paleontological party under the supervision of Mrs. Margaret Johnston.

0 WITH THE COMING of May, the planet Jupiter continues to be the most prominent star or planet visible in the evening sky. It is the first to appear in the northwest as the sky darkens after sunset. It then moves toward the western horizon to set-about four hours after sundown on May 1, two hours earlier on the 31st. Jupiter's position in the constellation of Gemini, the twins, is shown on the accompanying maps. These maps depict the sky as it looks about 11:00 p.m. (your own kind of daylight saving time) on May 1, 10:00 at mid-month, and 9:00 at the end. Among the stars, the most prominent is Arcturus, shown high in the south in Bootes, the herdsman. Below it is Virgo, the virgin, with Spica, another star of the first magnitude. Above and to the right of Virgo shines Leo, the lion, with a star of similar brightness, Regulus. Low in the southeast stands part of Scorpius, the scorpion. The star close to the horizon, named Antares, is also of the first magnitude. At such a low altitude, however, so much of its light is absorbed by the earth's atmosphere that it appears considerably fainter. In Gemini, where Jupiter now stands, is Pollux, another first magnitude star, and nearby are two others of the same degree of brightness. One is Capella, to the right in Auriga, the charioteer; the other is Procyon, toward the left in Canis Minor, the lesser dog. These stars shine brilliantly in the winter evening sky, but are not visible on summer evenings. To take their place, however, two stars are rising in the northeast that will become very prominent on summer evenings. One is Vega, in Lyra, the lyre; the other is Deneb, in Cygnus the swan Like Antares, which will also become more conspicuous in summer evenings, Deneb is considerably dimmed because it is so low on the horizon. High in the north shines Ursa Major, the great bear, which includes the familiar Big Dipper. Here are the two pointers, whose direction indicates the north star, Polaris, which is part of Ursa Minor, the little bear-and also of the Little Dipper.