. Botany for high schools and colleges. Botany. 290 BOTANY, so on. The contucfc of an infected head of rye with an nnin- fectcd one is siillicient to communicate the fungus to the latter, and doubtless the conidia are also freely carried by the winds, and, to a certain extent, by insects. It appears that, in some cases at least, the germinating co- nidia produce, first, short hyphae, which bear a few small spores (s2)o?H(Ua, D, Fig. 198, x), which themselves g e r m i - nate, and "then pro- duce the sphaceha; it is doubtful, however, whether this always takes place. 384. — After the conid
. Botany for high schools and colleges. Botany. 290 BOTANY, so on. The contucfc of an infected head of rye with an nnin- fectcd one is siillicient to communicate the fungus to the latter, and doubtless the conidia are also freely carried by the winds, and, to a certain extent, by insects. It appears that, in some cases at least, the germinating co- nidia produce, first, short hyphae, which bear a few small spores (s2)o?H(Ua, D, Fig. 198, x), which themselves g e r m i - nate, and "then pro- duce the sphaceha; it is doubtful, however, whether this always takes place. 384. — After the conidial stage, the mycelium at the base of the ovary becomes greatly increased, and assumes a hard and compact form; it grows with a consider- able rapidity, and car- ries up on its summit the old sphacelia and the remains of the now-destroyed ovary (.4 and B^Y\g. 198)"^. The compact, horn- shaped, and dark-col- ored body which re- sults is called the sderotium ; that which is produced upon rye is from one to three centimetres long (.4 to in.) and from two to six millimetres in diameter (.08 to .25 in.) ; on other grasses it is usually of less size. The sclerotium occu- pies the position of the displaced ovary, and in the autumn. IK? ^# &-o-ooOo^' Fig. 198.—Claviceps purpurea. A, young sclero- tium, c, with old sphacelia, s ; p, the apex of the dead ovary of rye. B, upper part of A, in longitudinal sec- tion, showing sp'iacelia, s. C. transverse section through the sphacelia more highly magnified ; m, the mycelium, surrounded with the hyphai 6, hearino; co- nidia ; p, couidia fallen off ; to, the wall of the ovary. 2), germinating conidia, forming sporidia. x. A aiid B moderately" C and I) highly magnified.—After 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 Bessey, Charles Edwi
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