. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. inds the rays are the onlyperfect-flowered and seed-bearing florets in the head. It is seen,therefore, that even compositous heads may ^e androgynous. 180 LUSSOICS WITS PLANTS 205. The fact that the corolla of the discflorets is five-toothed may help us to understandwhat the single ray or strap of the ray florets is. These rays in both thedandelion and rud-beckia are minutelyfive-toothed at the suggests that theray represents the fiveparts of the corolla,and this is the cus-tomary in
. Lessons with plants. Suggestions for seeing and interpreting some of the common forms of vegetation. inds the rays are the onlyperfect-flowered and seed-bearing florets in the head. It is seen,therefore, that even compositous heads may ^e androgynous. 180 LUSSOICS WITS PLANTS 205. The fact that the corolla of the discflorets is five-toothed may help us to understandwhat the single ray or strap of the ray florets is. These rays in both thedandelion and rud-beckia are minutelyfive-toothed at the suggests that theray represents the fiveparts of the corolla,and this is the cus-tomary is evident that ifthe corolla of a floretwere to develop to sucha length, it could notspread equal-ly in all di-rections, asa mathematical calculation willprove; it therefore develops inone direction, as a leaf Another peculiarity ofthe rudbeckia, as compared with the dandelion, isthe absence of pappus. The pupil should now ex-amine the sunflowers; and he has probably alreadyhad experience with the barb-like bristles of thepitch-forks or stick-tights, which collect on the. fullers teasel. The dry,mature head used forteasing cloth. THE COMPOSITOUS TBIBJUS 181 This is clothing in a walk through a weedy field. Hewill soon be prepared to say that the pappus maybe either absent or very abundant, and may varyin character from a narrow rim on the top of theseed-like body to scales, barbs, bristles and plumes. 207. The disc floret in Fig. 173 has anotherpeculiarity in the presence of a scale {a).present in many compositous flowers,and, like nearly all scales, is homol-ogous with a leaf; one of thesescales subtends each floret, and thereby^we have another proof that the re-ceptacle of a composite head is reallya shortened branch, or a rachis. 207a. The pupil will now appreciate the form of it is common along roadsides in theEastern states. The flower-head would pass atonce for a composite, but the anthers are notsyngenesious, and there are other tech
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