Elementary botany . male plant of Marchantia polymorpha, showingcavities where the antheridia are borne. dicular to its surface we shall be able to unravel the mystery ofits interior. Here we see, as shown in fig. 258, that each oneof these little openings on the surface is an entrance to quite 228 MORPHOLOGY. a large cavity. Within each cavity there is an oval or ellip-tical body, supported from the base of the cavity on a shortstalk. This is an antheridium, and one of them is shown stillmore enlarged in fig. 259. This shows the structure of theantheridium, and that there are within several a
Elementary botany . male plant of Marchantia polymorpha, showingcavities where the antheridia are borne. dicular to its surface we shall be able to unravel the mystery ofits interior. Here we see, as shown in fig. 258, that each oneof these little openings on the surface is an entrance to quite 228 MORPHOLOGY. a large cavity. Within each cavity there is an oval or ellip-tical body, supported from the base of the cavity on a shortstalk. This is an antheridium, and one of them is shown stillmore enlarged in fig. 259. This shows the structure of theantheridium, and that there are within several angular areas,which are divided by numerous straight cross-lines into countlesstiny cuboidal cells, the sperm mother cells. Each of these, asstated in the former chapter, changes into a swiftly moving bodyresembling a serpent with two long lashes attached to its tail. 485. The way in which one of these sperm mother cells changes into thisspermatozoid is very curious. We first note that a coiled spiral body is appear-. Fig-. of antheridium of mar-chantia, showing the groups ofsperm mother cells. Fig. of marchantia,uncoiling and one extended, show-ing the two cilia. ing within the thin wall of the cell, one end of the coil larger than the other end terminates in a slender hair-like outgrowth with a delicate vesi-cle attached to its free end. This vesicle becomes more and more extendeduntil it finally breaks and forms two long lashes which are clubbed at theirfree ends as shown in fig. 260. 486. Archegonial plants.—In fig. 261 we see one of thefemale plants of marchantia. Upon this there are also verycurious structures, which remind one of miniature general plan of the archegonial receptacle (or female LI VER WOR TS: MA R CHA N TIA. 229 gametophore), for this is what these structures are, is similar tothat of the antheridial receptacle, but the rays are more pro-nounced, and the details of structure are quite different, as wes
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