. The elements of structural . artition. 24 ELEMENTS OF STRUCTURAL BOTANY. 30. Mallow. The round-leaved Mallow (Fig. 31) grows alongevery way side,and is a verycommon weedi n cultivatedgrounds. Pro-cure, if possible,a plant whichhas ripened itsseeds, as well asone in root of thisplant is of adifferent kindfrom those of thethree plants firstexamined. Itconsists of astout taperingpart, descending deep into the soil, from the surface ofwhich fibres are given off irtegularly. A stout root ofthis kind is called a tap-ruot. The Carrot is anotherexample. 31. The leaves are long-p
. The elements of structural . artition. 24 ELEMENTS OF STRUCTURAL BOTANY. 30. Mallow. The round-leaved Mallow (Fig. 31) grows alongevery way side,and is a verycommon weedi n cultivatedgrounds. Pro-cure, if possible,a plant whichhas ripened itsseeds, as well asone in root of thisplant is of adifferent kindfrom those of thethree plants firstexamined. Itconsists of astout taperingpart, descending deep into the soil, from the surface ofwhich fibres are given off irtegularly. A stout root ofthis kind is called a tap-ruot. The Carrot is anotherexample. 31. The leaves are long-pctioled, net-veined and in-dented on the edges. On each side of the petiole, atits junction with the stem, you will observe a little leaf-like attachment, to which the name stipule is i^resence or absence of stipules is a point of someimportance in plant-structure, and you will do well tonotice it in your examinations. You have now madeyourselves acquainted with all the parts that any leafhas, viz., blade, petiole and Fig. 34. ELEMENTS OF STRUCTURAL BOTANY. 25 32. Coming to the flower, olserve first that the partsof the calyx are not entirely separate, as in the flowersyou have already examined. For about half theirlength they are united together so as to form a upper half of each sepal, however, is perfectly dis-tinct, and forms a tooth of the calyx ; and the fact thatthere are five of these teeth shows us unmistakably thatthe calyx is made up of five sepals. We therefore speakof it as a (lamosepalous calyx, to indicate that the partsof it are coherent. As the calyx does not fall away when the other partsof the flower disappear, it is said to be jmsistent. , a, shows a persistent calyx. 33. At the base of the calyx there are three minuteleaf-like teeth, looking almost like an outer calyx. Acucle of bracts of this kind is called an iiaolucre. Thethree bracts under the flower of the Hepatica also con-stitute an involucre. As the bracts in the Ma
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1879
