. The Canadian field-naturalist. May, 1925] The Canadian Field-Naturalist 105. Figure 12.—TROPISMS OF GARRY OAKS. Characteristic apical elongation of terminal buds toward rock masses in the neighbourhood of the tree. After attainment of the apparent objective the normal growth-form is resumed. Local- tiy, Victoria, APICAL ELONGATION Rock in the environment of oak seems often to influence the direction of growth taken by the trees. There are many cases where an oak or one of its limbs bends over toward nearby rock and after attaining a certain point resumes more vertical growth. Frequently
. The Canadian field-naturalist. May, 1925] The Canadian Field-Naturalist 105. Figure 12.—TROPISMS OF GARRY OAKS. Characteristic apical elongation of terminal buds toward rock masses in the neighbourhood of the tree. After attainment of the apparent objective the normal growth-form is resumed. Local- tiy, Victoria, APICAL ELONGATION Rock in the environment of oak seems often to influence the direction of growth taken by the trees. There are many cases where an oak or one of its limbs bends over toward nearby rock and after attaining a certain point resumes more vertical growth. Frequently, the stems are quite procumbent for a while and these bendings are not in the direction of prevailing winds, etc. Figure No. 12 gives an illustration of one of the many phases of the characteristic. It shows a pro- nounced bending over of the stem and limbs of an oak till certain points in the rock close at hand have been reached. Then the branches curve sharply upward and assume the normal growth- form of the oak. FURTHER OBSERVATIONS ON CANADIAN EUPHYLLOPODA By FRITS JOHANSEN EUBRANCHIPUS GELIDUS HE TEMPERATURES around Ottawa for the first half of April, 1924, were between 26°F. and 48°F., except for the minimum of 14°F. on March 31-April 1st., and the maximum of 52°F. on April 4th. The weather was mostly clear, except for snow on April 25th; rain on the 6th, 9th and 13th, and some overcast days. On April 13th, I looked for Phyllopods (E. gelidus) in all the pools and ponds between Fairy Lake and Wrightville (Hull), Que., where I found them last year; but I could discover no hatched larvae, though the pools were ice-free, and the snow had almost disappeared from the fields here. Air temperature at 38|°F., of water in pools 44°F.; overcast, rainy and windy. On April 16-17th, the temperatures were between 28°F. and 54°F., and the weather clear. During these two days most of the hibernating eggs of E. gelidus hatched in the ponds around Ottawa. April 18-19th
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