The Egyptian boll worm (Earias insulana) is the most important insect pest in Egypt and occurs also in other parts of Africa.
See generally Franz Boll, Sphaera (Leipzig, 1903); also the bibliographies to ASTROLOGY and BABYLONIAN AND ASSYRIAN RELIGION.
The researches of Bouche-Leclercq, Cumont and Boll have enabled us to fix with a considerable degree of definiteness the middle of the 4th century B.C. as the period when Babylonian astrology began its triumphal march to the west, invading the domain of Greek and Roman culture and destined to exercise a strong hold on all nations and groups - more particularly in Egypt - that came within the sphere of Greek and Roman influence.
No certain remedy is known for the destruction on a commercial scale of the boll weevil, but every effort has been made in the United States to check the advance of the insect, to ascertain and encourage its natural enemies, and to propagate races of cotton which resist its attacks.
Mr Cook also found that the boll weevil was attacked, killed and eaten by an ant-like creature, the " kelep."
The boll worm is most destructive in the south-western states, where the damage done is said to vary from 2 to 60% of the crop. Taking a low average of 4%, the annual loss due to the pest is estimated at about 1 - 2,500,000, and it occupies second place amongst the serious cotton pests of the U.S.A. The boll worm is widely spread through the tropical and temperate zones.
Indian boll worms include the same species, and the closely related Earias fabia, which also occurs in Egypt.
" Boll rot," or "Anthracnose," is a disease which may at times be sufficiently serious to destroy from ro to 50% of the crop. The fungus which causes it (Colletotrichum gossypii) is closely related to one of the fungi attacking sugar-cane in various parts of the world.
The damage may be only slight, or the entire boll may ripen prematurely and become dry and dead.
Special interest attaches to experiments made in the United States to endeavour to raise races of cotton resistant to the boll weevil.
The boll-weevil, preying on the cotton, is the most noxious of the insects.
See the Acta Sanctorum, Boll., 1st October; and the Register of Thomas de Cantilupe, with introduction by W.
Eine Inselstudie (Stuttgart, 1893); Edwin Muller, Die Insel Rugen (17th ed., Berlin, 1900); Schuster, Fuhrer durch die Insel Rugen (7th ed., Stettin, 1901); Boll, Die Insel Rugen (Schwerin, 1858); O.
The fruit or boll is round, containing five cells, each of which is again divided into two, thus forming ten divisions, each of which contains a single seed.
See Boll, Chronik der Vorderstadt Neubrandenburg (1875).
Bouche-Leclercq, L'Astrologie grecque (Paris, 1899), with a full bibliography; Franz Boll, Sphaera (Leipzig, 1903); Franz Cumont, Catalogus Codicum Astrologorum Graecorum (Brussels, 1898; 7 parts published up to 1909); Franz Boll, "Die Erforschung der antiken Astrologie" (in Neue Jahrbiicher fur das klassische Altertum, Band xxi.
The cotton boll weevil (Anthonomus grandis), a small grey weevil often called the Mexican boll weevil, is the most serious pest of cotton in the United States, where the damage done by it in 1907 was estimated at about £5,000,000.