The structure & development of the mosses and ferns (Archegoniatae) . n the former group are two divisions, those which,like E. arvense and E. telmateia, have the fertile and sterilebra,nches different, and those where they are alike, E. liinosuni(.Fig. 242, A). In the former group some species, E. pratense,have the fertile stems at first colourless, but afterwards formingchlorophyll and developing branches. In Hippochcete, whichincludes among American species E. Jiiemale, E. robustum, and E. scirpoides (Fig. 272, B), the aerial branchesare all similar and often are quit
The structure & development of the mosses and ferns (Archegoniatae) . n the former group are two divisions, those which,like E. arvense and E. telmateia, have the fertile and sterilebra,nches different, and those where they are alike, E. liinosuni(.Fig. 242, A). In the former group some species, E. pratense,have the fertile stems at first colourless, but afterwards formingchlorophyll and developing branches. In Hippochcete, whichincludes among American species E. Jiiemale, E. robustum, and E. scirpoides (Fig. 272, B), the aerial branchesare all similar and often are quite unbranched. The foliarsheaths show considerable variation. In the fertile stems of (Fig. 227) they are extremely large and the ribs veryprominent, but the separate leaves are not all distinct at theapex, but the sheath splits into a few very deeply cleft pointedlobes. In the sterile shoots, however, and in all the stems ofmost species, the teeth are very distinct and the foliar sheathmuch shorter. The number of teeth varies from three in 1 Milde (I).. Fig. 242.—a, Equisetuvi limosum {L.), xh; B, E. scirpoides (Michx.), X2. CHAP, xiii EQUISETINEjE 459 E. scirpoides, to thirty to forty, or even more, in E. telinateia andE. robiistuvi. Fossil EquisetinecB To this class are usually assigned two groups of fossilplants, one belonging to the Equisetaceae, and represented bythe genus Eqiiisetites, which evidently was very close to thegenus Equisetum, if not identical with it. The other group, theCalamarieae, differed in some respects from the living forms, andthere is much diversity of opinion about their real best known members of this order are the Calamiteaj,whose anatomical structure is well known. Cormack ^ hasrecently made a comparison of the structure of these withEquisetuin, and comes to the conclusion that the type ofstructure is essentially the same. The general points ofdifference are the completely separate leaves of the Calamites,the frequen
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Keywords: ., bookcentury1800, bookdecade1890, bookidstructuredev, bookyear1895
