Organography of plants, especially of the archegoniatae and spermaphyta . longitudinal section through the ripe capsule ofAneura pinguis. The elaterophore appears as atissue-mass projecting downwards from the upperwall of the capsule and the loose elaters are distri-buted in a radiating manner in the space betweenthe spores. The elaterophore splits later into fourparts, and the lines of separation are very earlyrecognizable. The cells of the elaterophore have semi-annular thicken-ings, and the lowermost of the cells frequently grow into pointed cells likeelaters. Between these projections of t
Organography of plants, especially of the archegoniatae and spermaphyta . longitudinal section through the ripe capsule ofAneura pinguis. The elaterophore appears as atissue-mass projecting downwards from the upperwall of the capsule and the loose elaters are distri-buted in a radiating manner in the space betweenthe spores. The elaterophore splits later into fourparts, and the lines of separation are very earlyrecognizable. The cells of the elaterophore have semi-annular thicken-ings, and the lowermost of the cells frequently grow into pointed cells likeelaters. Between these projections of the elaterophore, as well as inother places, the ends of a number, not all, of the free elaters lie. Thecapsule opens by four valves which assume a nearly horizontal position, andthe mass of spores and elaters divides similarly into four parts. Each oneof the four masses thus formed and lying upon a valve undergoes a torsionof about 90° at its point of attachment to the elaterophore, and thus thespore-mass upon each valve stands erect. An energetic throwing off of the. Fig. 87. Aneura pinguis. Riperapsule in longitudinal the summit the elaterophorehangs into the spore cavity in whichare many spores and elaters. Mag-nified. Its nutritive function in the juvenile stage of the sporogonium will be referred to p. 103. 102 THE SPOROGONIUM IN HEPATIC A E spores now begins, and in about five minutes there is hardly a single elaterleft upon the elaterophore. It is evident that two things are achieved bythis arrangement: firstly, the spore-masses being raised above the sporangialwall can be shot out further into the environment, and secondly, the elon-gated cylindric form of the sporangium results in a more thorough dis-charge of the spores ; and in correspondence therewith we see that theelaterophore is more developed the longer the capsule ^. II. Elaters are not, or not usually -, Organs for the Ejec-tion OF Spores, but serve to hold the Mass of Spores. Features
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