0 from Oltmanns, Morphologie u.
It is interesting to know, on the authority of Oltmanns, that when the oosphere is forming in the oogonium of Vaucheria, there is a retrocession of all the included nuclei but one.
(A from Cooke, British Freshwater Algae, by permission of Kegan Paul, Trench, Triibner and Co.; C, E, F, G, H, K from Engler and Prantl, by permission of Wilhelm Engel mann; B 1 from Vines, by permission of Swan Sonnenschein and Co.; B2, D from Oltmanns, by permission of Gustav Fischer.) protoplasts.
(A, B, C, D, E, H, L, M, P, from Engler and Prantl, by permission of Wilhelm Engelmann; F, G, K, 0, from Oltmanns, by permission of Gustav Fischer; Q, from by permission of the Clarendon Press; N 1, N 2, from Hauck, by permission of Eduard Kummer.) the brown colouring matter which is added to chlorophyll is identical with phycophaein; two varieties of it have been termed phycopyrrin and peridinine.
Oltmanns has recently re-investigated the phenomena in this plant, among others, and has shown that the nucleus of the cell which is being preyed upon recedes to the wall and gradually atrophies.
(A, C, D, E, F, G, H, K, L, M, P, Q, from Oltmanns, by permission of Gustav Fischer; B, N, 0, R, from Engler and Prantl, by permission of Wilhelm Engelman,) mass and from it all the nuclei of the carpospores are thus derived.
Algae life, Oltmanns distinguishes bush-forms, whip forms, net-forms, leaf-forms, sack-forms, dorsi-ventral forms, and cushions, plates and crusts.
Oltmanns, Morphologie and Biologie der Algen (Jena, Band i.
Oltmanns, " Beitrage zur Kenntniss der Fucaceen," Bibliotheca botanica, xiv.
Oltmanns, Zur Entwickelungsgeschichte der Florideen," Botanische Zeitung (1898); R.