. Journal of botany, British and foreign. ctive forms ;I, Morei producing long slender setaceous leaves, floating on thesurface of water, as they frequently do at Lake Bray; I. lacustrisshort stiff subfalcate leaves, remaining under water. Although our plant differs in so many particulars from thenormal state of I. lacustris, it may be only a remarkable abnormalform of it. It is certainly much more distinct from it thanI. echinospora is, which differs in no essential particulars, fartherthan the echinate macrospores and generally smaller more slendersetaceous leaves. It may be the fact that in
. Journal of botany, British and foreign. ctive forms ;I, Morei producing long slender setaceous leaves, floating on thesurface of water, as they frequently do at Lake Bray; I. lacustrisshort stiff subfalcate leaves, remaining under water. Although our plant differs in so many particulars from thenormal state of I. lacustris, it may be only a remarkable abnormalform of it. It is certainly much more distinct from it thanI. echinospora is, which differs in no essential particulars, fartherthan the echinate macrospores and generally smaller more slendersetaceous leaves. It may be the fact that in Northern Europe we have only onetrue species, I. lacustris; I. ecliinospura and the present plant,I. Morei, being the extremes of forms of that species ? However, theparts which afford specific characters in this genus being so few,and some of them, as we have seen, not very constant, it may betaken for granted that the limits of true species of Isoetes are notyet fully settled. But, either as a species or variety, I trust this H. Olson.]it>i Mmtem Bros irtqj. THE *PRO-EMBKYO OF CHARA. 355 remarkable plant will bear the name of my colleague, A. , Esq., who first called attention to it, and who has con-tributed in so many instances to the furtherance of British botany. Desceiption of Tab. 199. — Isoetes Morei, D. Moore, from specimenscollected at Lough Bray, Ireland. 1. A complete plant. 2. Vertical section ofthe corra. 3. Transverse section of the same. 4, Lower portion of a leaf,showing macrosporangium, veil and lingula. 5. Transverse section of micro-sporangium. 6. Transverse section of leaf. 7. Macrospores. [—In section No. 4 the lingula is shewn too narrow at hase, withmargins more entire than they usually are.] THE PKO-EMBKYO OF CHARA: AN ESSAY IN MORPHOLOGY. By Sydney H. Vines, , , , Fellow and Lecturer of Christs College, Cambridge. It is to the researches of Pringsheim^ that we are indebted forour knowledge of the fact that the
Size: 1195px × 2092px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthortri, bookcentury1800, bookdecade1860, booksubjectplants
