Organography of plants, especially of the archegoniatae and spermaphyta . ear independently of oneanother. W. H. Lang has recently ob-sen-ed sporangia upon apogamous pro-thalli, and if we must assume that theseare placed upon an extremely rudimen-tary sporophyte we have a very re-markable shortening of the developmentwhich is of extreme interest for the theoryof inheritance and development. Wemight find in these facts a support to theassumption that for each organ or com-plex of organs there exists a definitematerial carrying the inheritance, whichusually appearing late, may, under ab-normal r
Organography of plants, especially of the archegoniatae and spermaphyta . ear independently of oneanother. W. H. Lang has recently ob-sen-ed sporangia upon apogamous pro-thalli, and if we must assume that theseare placed upon an extremely rudimen-tary sporophyte we have a very re-markable shortening of the developmentwhich is of extreme interest for the theoryof inheritance and development. Wemight find in these facts a support to theassumption that for each organ or com-plex of organs there exists a definitematerial carrying the inheritance, whichusually appearing late, may, under ab-normal relationships, appear early. Thesame may be said in a certain sense alsoof the anatomical relationships. Tracheids,for example, which normally belong onlyto the sporophyte, may appear also inthe apogamous prothalli of Filicineae, although the formation of the organs of young pfants afise. After Heim. the sporophyte is not reached. It even appears in apogamy that there is a jumbling together of the different organs such as has been shown to occur in other malformations \. Fig. i6o. Doocha caudata. Apogatny in aprothallus. Papillae are seen, and upon these See Part I, p. 196. THE SPOROPHYTE IN THE PTERIDOPHYTAAND SPERMOPHYTA There is so great a resemblance in the formation of the organs of thesporophyte in the Pteridophyta and in the Spermophyta that we may takethe two groups together. In the typical cases we find that the vegetativeorgans are roots and leafy shoots, and the reproductive organs are spor-angia^ in both groups or aggregate of groups, and whilst there are manydifferences, both in the external configuration and in the inner structure ofthese organs in the two groups, yet in essentials they are alike. THE ORGANS OF VEGETATION INTRODUCTION In the first part of this book I have pointed out the general featuresof the vegetative organs. If we distinguish root and shoot as fundamentalorgans this is only based upon the fact that they are the most importantand are the most ge
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