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Proc. Acad. Nat. Sc. Philadelphia June 16 1874 & July 23d. 1875.— 3 species of Euphorbia & Portulaca oleracea, which naturally produce "normally prostrate or procumbent" branches, & then become assume an erect habit" (that is no doubt not geotropic) when attacked by an Œcidium.

Mr Th. Meehan

add after [illeg]- f Fir-trees.

[Movement in plants, p. 189: "According to Mr. Meehan,* the stems of three species of Euphorbia and of Portulaca oleracea are "normally prostrate or procumbent;" but when they are attacked by an Aecidium, they "assume an erect habit." Dr. Stahl informs us that he knows of several analogous cases; and these seem to be closely related to that of the Abies. The rhizomes of Sparganium ramosum grow out horizontally in the soil to a considerable length, or are diageotropic; but F. Elfving found that when they were cultivated in water their tips turned upwards, and they became apogeotropic. The same result followed when the stem of the plant was bent until it cracked or was merely much bowed.†
No explanation has hitherto been attempted of such cases as the foregoing,—namely, of secondary radicles growing vertically downwards, and of lateral shoots growing vertically upwards, after the amputation of
* 'Proc. Acad. Nat. Sc. Philadelphia,' June 16th, 1874, and July 23rd, 1875."]