. The ecology and life history of the common frog (Rana temporaria temporaria). Rana temporaria. EXTERNAL FACTORS ON THE SPAWN DATE 141 this region of the diagram (Fig. 38), and nowhere else, sunshine acceler- ates spawning, In the other parts of the diagram, where there would be some rim-off, sunshine delays spawning. These effects, I must point out, occur in this month, when the frogs are liibcrnating, mosdy in the dark. Mi, Sunshine and Temperature. Much the same occurs when sunsliinc and temperature are used as joint factors (Fig, 39). At low ISOPHENES IN YEAR-DAYS. Fig. 39. Joint Function
. The ecology and life history of the common frog (Rana temporaria temporaria). Rana temporaria. EXTERNAL FACTORS ON THE SPAWN DATE 141 this region of the diagram (Fig. 38), and nowhere else, sunshine acceler- ates spawning, In the other parts of the diagram, where there would be some rim-off, sunshine delays spawning. These effects, I must point out, occur in this month, when the frogs are liibcrnating, mosdy in the dark. Mi, Sunshine and Temperature. Much the same occurs when sunsliinc and temperature are used as joint factors (Fig, 39). At low ISOPHENES IN YEAR-DAYS. Fig. 39. Joint Functional Regression Diagram, Showing the Relation between Sunshine and Temperature and Spawn Date, for the Month Mi Below about 14 per cent of sunshine, spawning is earlier when there is more sunshine, but above these low amounts, sunshine always retards spawning. Note the late dates when it is hot and sunny, in the top right hand part of the diagram. temperatures, the evaporating property of sunshine is less prominent than at high temperatures. At low temperatures, sunshine accelerates spawning. At all other temperatures, it retards. Taken in conjunction with the other evidence, this seems convincing support for the. 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
