. The microscope and its revelations. nging to thePkceosporece, are included many ofthe largest of the seaweeds, chieflynatives of southern seas, the frondoften attaining enormous dimen-sions, and exhibiting rudimentarydifferentiation into rhizoids ororgans of attachment, stem, andleaves. Such are Lessouia, whichgrows to a great height and re-sembles a branching tree with pendent leaves two or three feetlong ; Macroci/stls, where the stalk like base of each branch of theleaf is hollowed out into a large pear-shaped air-bladder ; N&reocystis,Laminaria, and others. In the Fucaceae the generative
. The microscope and its revelations. nging to thePkceosporece, are included many ofthe largest of the seaweeds, chieflynatives of southern seas, the frondoften attaining enormous dimen-sions, and exhibiting rudimentarydifferentiation into rhizoids ororgans of attachment, stem, andleaves. Such are Lessouia, whichgrows to a great height and re-sembles a branching tree with pendent leaves two or three feetlong ; Macroci/stls, where the stalk like base of each branch of theleaf is hollowed out into a large pear-shaped air-bladder ; N&reocystis,Laminaria, and others. In the Fucaceae the generative apparatus is contained in theglobular conceptacles, which are usually sunk in the tissue near theextremities of the fronds. In some species, as FUCKS plati/carpus,the same conceptacles contain both antherids and oogones ; inothers these two sexual elements are disposed in different conceptacleson the same plant; whilst in the commonest of all, F. vesicnlosus(bladder-wrack), they are limited to different individuals. When a s s 2. FKI. 469.—Process of conjugationin Ectocarpus siliculosiis. (FromViness Physiology.) I. a-f, thefemale zoiispore coming to rest ;II., the female zoijspore at rest,surrounded by male zoiispores ;III. a—c, fusion of male and femalezoiJspores. 628 MICROSCOPIC FORMS OF VEGETABLE LIFE—THALLOPHYTES section is made through one of the flattened conceptacles of , its interior is seen to be a nearly globular cavity (fig. 470).lined with hairs, some of which are greatly elongated, so as toproject through the pore by which the cavity opens on the these are to be distinguished, towards the period of theirmaturity, certain filaments (fig. 471, A), the anther ids, whosegranular contents acquire an orange hue, and gradually shapethemselves into oval bodies (B), each with an orange-coloured spotand two vibratile cilia of unequal length, placed laterally, which,when discharged by the rupture of the containing cell, have for a time a rapid, i
Size: 1210px × 2065px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectmicrosc, bookyear1901
