Page:The American Cyclopædia (1879) Volume XIII.djvu/496

 480 PHYLLOXERA PHYSALIS a few eggs, which are of two sizes, and which produce males and females, organized and con- structed precisely as those born of the winged females, and like them producing the soli- tary impregna- ted egg. We have therefore the spectacle of an underground insect possessing the power of continued exist- ence, even when confined to its subterranean re- , treats. It spreads a, &. Mother gall louse, dorsal and. f , ventral views. Natural size indi- * n the Wingless cated between them. state from vine to vine, and from vineyard to vineyard, when these are adjacent, either through passages in the ground itself or over the surface. At the same time it is able, in the winged condition, to emigrate to much more distant points. The winged females be- gin to appear in July, and continue to issue from the ground until vine growth ceases. They are much more abundant in August than during any other month, and on certain days literally swarm. Every piece of root a few inches long and having rootlets, if taken from an infested vine at this season, will present a number of pupae; and an ordinary quart pre- serve jar, filled with such roots and tightly closed, will furnish daily for two or three weeks a dozen or more of the winged females, which gather on the side of the jar toward the light. Occasionally individuals under cer- tain conditions abandon their normal under- ground habit, and form galls upon the leaves FIG. 8. Under Side of Leaf covered with Galls. of certain varieties of grape vine. No spe- cies of vine is entirely exempt from the at- tacks of the insect in one form or another; yet many indigenous American vines resist its attacks so far that they are never seriously affected. The gall lice are found on all spe- cies, but least on the European vine. (vitis mnifera) and most on the river bank grape (best known as cordifolia), and especially on the Clinton and Taylor. The root lice are most injurious to the European vine, and least so to our summer grape ( V. cestivalis) and the scup- pernong ( V. vulpina), on the roots of which last it has not yet been discovered. The most susceptible native varieties, such as Catawba, lona, Delaware, and Goethe, belong to the northern fox ( V. Idbruscd). Just as the punc- ture of the gall louse causes an abnormal swell- ing of the leaf, so that of the root louse causes knots and swellings on the roots. These swell- ings, which generally begin at the tips of the rootlets, where there is excess of plasmatic and albuminous matter, eventually rot, and the lice betake themselves to fresh ones; the living tis- sue being necessary to the existence of this as of all plant lice. During the first year of attack there are scarcely any outward manifestations of disease, though the fibrous roots, if exam- ined, will be found covered with nodosities, particularly in the latter part of the growing season. The disease is then in its incipient stage. The second year all these fibrous roots vanish, and the lice not only prevent the for- mation of new ones, but settle on the larger roots, which also eventually become disorgan- ized and rot. At this stage the outward symp- toms of the disease first become manifest, in a sickly, yellowish appearance of the leaf, and a reduced growth of cane; and about the third year the vine dies. When the vine is about dying it is generally impossible to discover the cause of the death, the lice, which had been so numerous the first and second years of in- vasion, having left for fresh pasturage. The phylloxera is attacked by several enemies, few of which, however, reach it below ground. A host of remedies have been tried, but, with the exception of submersion and the use of sand and fertilizers, especially those rich in alkali, few are available in practical experience. See Prof. Eiley's sixth annual "Report on the Insects of Missouri " (1874). PHYSALIS (G-r. Qoadtts, a bladder, in reference to the inflated calyx), a genus of annual and perennial herbs, of the solanacece or nightshade family, comprising about 50 species, several of which are North American and two or three cultivated in gardens. Those in cultivation, though having perennial rootstocks, are treat- ed as annuals; they have branched spread- ing stems, which with the triangular or some- what heart-shaped leaves are viscid-hairy; the solitary flowers are nodding on extra-axillary peduncles, with a five-cleft calyx, and a green- ish white or yellowish corolla, between wheel- shaped and funnel-formed; five erect stamens, and a two-celled ovary, which when ripe comes a two-celled, juicy, edible berry; flowering and during the development of tl fruit, the calyx grows very rapidly, and