. Beginners botany. Botany. 174 ' fruits are agreeable as luiman food, arid some of them have been greatly enlarged or " improved " by the arts of the cultivator. The seeds are usually indigestible. Burs.— Many seeds and fruits bear spines, hooks, and hairs, which adhere to the coats of animals and to clothijis;. The burdock has an involucre with hooked scales, contain- iiig the fruits inside. The clotbur is also an involucre. Both are composite plants, allied to thistles, but the whole head, rather than the separate fruits, is transported. In some com- posite frui
. Beginners botany. Botany. 174 ' fruits are agreeable as luiman food, arid some of them have been greatly enlarged or " improved " by the arts of the cultivator. The seeds are usually indigestible. Burs.— Many seeds and fruits bear spines, hooks, and hairs, which adhere to the coats of animals and to clothijis;. The burdock has an involucre with hooked scales, contain- iiig the fruits inside. The clotbur is also an involucre. Both are composite plants, allied to thistles, but the whole head, rather than the separate fruits, is transported. In some com- posite fruits the pappus takes the form of hooks and spines, as in the " Spanish bayonets " and " pitch- ; Fruits of various kinds are known as "stick tights," as of the agrimony and hound's-tongue. Those who walk in the woods in late sum- mer and fall are aware that plants have means of disseminating them- selves (Fig. 252). If it is impossible to iden- tify the burs which one finds on clothing, the seeds may be planted and specimens cf the plant may then be grown. Suggestions. —174. What advantage is it to the plant to have its seeds widely dispersed? 175. What are the leading ways in which fruits and seeds are dispersed? 176. Name some explosive fruits. 177, Describe wind travelers. 178. What seeds are car- ried by birds? 179. Describe some bur with which you are familiar. 180. Are adhesive fruits usually dehiscent or indehis- cent? 181. Do samaras grow on low or tall plants, as a rule? 182. Are the cotton fibres on the seed or on the fruit? 183. Name the ways in which the common weeds of your region are disseminated. 184. This lesson will suggest other ways in which. Fig. 252. —Stealing a Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Bailey, L. H. (Liberty Hyde), 1
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectbotany, bookyear1921