. Cacti. Cactus. CACTI 19 flowers like other plants, it is true, but much more abundantly from the cushions on the stems. This secretion is so abundant that it dries into a globule of clear crystalline sugar on each pulvinus or cushion wherever there are no summer rains to wash it off. The woody system is as variable as the plants themselves. It may be made up of a cylinder of woody strands, or a mesh, or lacework, with the modified buds at the intersections of the strands. The fruits are of great interest. They are more clearly modified stems than those of almost any other plant. They bear ru
. Cacti. Cactus. CACTI 19 flowers like other plants, it is true, but much more abundantly from the cushions on the stems. This secretion is so abundant that it dries into a globule of clear crystalline sugar on each pulvinus or cushion wherever there are no summer rains to wash it off. The woody system is as variable as the plants themselves. It may be made up of a cylinder of woody strands, or a mesh, or lacework, with the modified buds at the intersections of the strands. The fruits are of great interest. They are more clearly modified stems than those of almost any other plant. They bear rudimentary leaves and cushions of spines like the stems. They may be sessile on the plant or actually sunken into its tissues. They may mature. Figure 1.—Two contiguous cushions on the edge and side of a joint of prickly pear : a, Spines; b, bristles ; c, spicules ; d, wool. The bristles differ from both spines and spicules and are sometimes referred to as fugacious spines at the end of the season, or they may remain attached to the plants indefinitely. They are usually single, but commonly proliferate into a large pendent cluster which remains perennially attached. ATTRACTIVE INVESTIGATIONS WITH CACTUS SUBJECTS Very little attention has been given to the breeding of cacti other than the genus Opuntia. Doubtless it is here that the quickest and most profitable results are to be obtained. But what can be accom- plished in other groups has not been studied much. The prickly pears are, however, very plastic, and variable hybrids are easily obtained. It has occurred to the writers that an investi- gator so situated that he can devote a liberal space to their culture might bring together some very instructive data from the study of a large number of crosses of these easily modified 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 re
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Keywords: ., bookauthorgri, bookcentury1900, bookdecade1920, booksubjectcactus
