. The ecology and life history of the common frog (Rana temporaria temporaria). Rana temporaria. EXTERNAL FACTORS ON THE SPAWN DATE 127 Q. How do you know that? A. Because, although it was warm enough, they did not spawn. One has to break through this somehow. If in a fairly small area with a climate that does not differ much from one part to another, one set of frogs spawn, it seems reasonable to suppose that the breeding season has begun. To assume after this date that some other set of frogs is not physiologically ripe is a form of. o |9?6FEB 6 YEAR-DAY 11 16 21 26 3 8 13 18 23 28 42 47 52
. The ecology and life history of the common frog (Rana temporaria temporaria). Rana temporaria. EXTERNAL FACTORS ON THE SPAWN DATE 127 Q. How do you know that? A. Because, although it was warm enough, they did not spawn. One has to break through this somehow. If in a fairly small area with a climate that does not differ much from one part to another, one set of frogs spawn, it seems reasonable to suppose that the breeding season has begun. To assume after this date that some other set of frogs is not physiologically ripe is a form of. o |9?6FEB 6 YEAR-DAY 11 16 21 26 3 8 13 18 23 28 42 47 52 57 62 67 72 77 82 87 Fig. 29. Chart Showing Maximum and Minimum Temperature, Maximum and Minimum Humidity, and Rainfall for February and up to the Last Date of Spawning in the Area Within 50 Miles of London, for the Year 1926 Note that this year was early, and that February was wet. The spawning season itself was dry. Note also that much of the spawning took place in a period of falling temperature. In this and other charts, the spawn records are indicated at the top, each unit indicating one report. Rainfall shown is that of the day that is indicated plus that of the previous night. Special pleading that ought not to be admitted without some defmite justification. With this in mind, it can easily be seen from the charts (Figs. 29-32) that although sometimes spawning takes place in warm weather, or after a period of rising temperatures, it does not always do so. For example, there was considerable spawning during the cold weather between 7th and 17th March 1928, when the temperatures. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Savage, Ronald Maxwell. New York, Hafner Pub. Co.
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Keywords: ., bookcentury1900, bookcollectionbiodiv, booksubjectranatemporaria
