GLOSSAEY. 



393 



plete (let'ormation of tlie leaves, which 

 thicken, curl, twist, and swell, assuming a 

 pale yellow to rose tint. Wlieu the disease 

 reaches a certain pitch, the young branches 

 .are also invaded and deforuied. The mycelium 

 of the fungus which causes this disease is very 

 ramified ; it spreads on the surface of the 

 epidermis under the cuticle, fornung a sort 

 of perforated membrane. It applies itself 

 wholly against the nourishing cells and ex- 

 tends itself in the space between tlie cells. 

 By the action of the mycelium the cells of tlii> 

 epidermis and of the pareiicli\iua multiiily 

 in an abnormal way. There is thus pro- 

 duced a homogeneous fleshy tissue deprived 

 of chlorophyll which forms characteristic 

 .swellings. The mycelium gives out asci at 

 a certain point wliich traverse the cuticle, 

 .and impart to the deformed leaves a velvety, 

 whitish appearance. The spores developed 

 in the interior of the asci are projected out- 

 .side, through a transversal aperture. They 

 "are white sort of leavens, wliich placed in 

 water multiply indefinitely by Inidding. 

 The rust does not propagate itself from year 

 to year by means of the spores, liut chiefly 

 by the mycelium. The latter, which is per- 

 ennial, hibernates in the buds whence it pene- 

 trates into the young leaves. The periodical 

 appearance of leaf curl causes great damage 

 to the tree and finally kills it. Leaf curl 

 therefore causes great damage. The bites of 

 plant lice sometimes cause an analogous de- 

 formation of the leaves. 



Exo.\scus PRONi (pocket or bladder 

 jjlums).— This fungus is in all points com- 

 parable with the Krtiuscus d"forinaas which 

 produces the leaf curl of the peach, but 

 instead of deforming the leaves it lodges in 

 the pistils of the flowers which assume under 

 its influence an extraordinary development. 

 The pistil is converted into a sort of liollow 

 elongated pocket. Tlie mycelium is hardy 

 and passes the winter under the young 

 branches whence it penetrates in the spring 

 into the young pistils of the fiowers. 



FiDONl.v PiNAUi.v (phalena of the pine).— 

 Dark brown butterfly ; the upper wings of 

 the female are stripect with yellow bands, 4 

 centimetres from tip to tip, the male 3 centi- 

 metres. The caterpillars gnaw pine neeiUes 

 which they generally cut tlirough the middle 

 and let one-half fall to tlie ground. The 

 ravages last from August to October. The 

 caterpillar is green with white and yellow 

 longitudinal lines. It reaches ,3 centimetres 

 in length. It descends the length of the 

 trunk in winter to metamorphose itself in 

 the moss of the .soil. 



Finger and Toe, see Anbury and 

 Plas.modiophora, Brassic.e. 



Fdmagine. Capiwdium (.smut of fruit 

 trees).— Fumagine is the term applied to 

 the lilack coating which appears on certain 

 plants infested by plant lice or cocliineals 

 '{scale insects). Ttiis coating is formed by the 

 black mycelium of a fungus which lives 

 solely on the .saccharine liquid, the honey- 

 dew, which the insects project on the leaves 

 ■without ever penetrating the epidermis to 



extract food. The damages caused by this 

 fungus are serious because they injure the 

 regular functions of the leaf, and they, 

 moreover, soil the fruit which they render 

 unfit for fooil. The cochineal and conse- 

 quently the fumagine are very injurious to 

 trees especially in orchards. 



Fusarium NOV. sp. (flax disease). — The 

 exhaustion of the soil in flax cultivation so 

 common in America is due, according to the 

 researches of Bolley, to the presence of a fun- 

 ;4us which, ill uttackiiiu \\:\\ plants, weakens 

 them and c\-ciitu:illv c.■l!l^cs tlicm to perish; 

 growth IS stopped, the shouts fiide and finally 

 liry up. 



FusiCLADlOM CERASI (black spots of the 

 cherry).— This fungus, very analogous to the 

 foregoing, attacks cherries on which it pro- 

 duces small black-gi-een velvety spots. The 

 cherries attacked late in the .season ripen 

 without their taste being altered. However, 

 when the fungus invades the young cherry 

 of the size of a pea, the latter dries up, 

 browns, and withers liefore ripening. 



FcsicIjADIL'm pikinum (pear scab, pear 

 holes). Fiislrladiuiii ih-nfritli'um (apple .scab, 

 holes of the apple).- -These two fungi are 

 very analogous, and do the same damage, 

 the one on the peav-trcc, the other on the 

 apple-tree. The Fn^irlinli inn jiin'/iniii at- 

 tacks the leaves, branches, and fruits of the 

 pear-tree. Numerous dark spots appear on 

 the leaves which become pulverulent and of 

 a black olive-green. On the young shoots the 

 fungus also forms black spots and speckled 

 places which become more or less tleep holes 

 on the branches, kiU their extremities and 

 ilry up the buds. The fruits covered with 

 black spots are soon deformed and holed as 

 they gi'ow, thus losing all their value. 

 Certain varieties, like the /hii/enne d'hiver, 

 are particularly sought after liy this fungus. 

 Black conidiophora are to be seen on examin- 

 ing the leaves as well as the Ijrauches and 

 fruits ; they are formed on the mycelium 

 which extends into the superficial tissues of 

 the organs attacked ; numerous spores fall 

 from their summit. The conidia germinate 

 very easily in a few hours when they fall 

 into a drop of water ; their gerniiuative tube 

 glides some time on the surface of the fruit, 

 there ramifies, and finally pierces the epi- 

 dernns where it chiefly grows without fixing 

 it.self deeply into the neighbouring tissue. 

 In winter spermagonia are formed on the 

 branches which transmit the <lisi-ase from 

 one year to another. .Moi-t si^asons greatly 

 favour this disease. Fnsirhid nun il, „t riticwm 

 produces lilaek velvety olive-greeii-covered 

 spots on the leaves of the apple-tree, on the 

 fruits brown or dark spots, .sometimes iso- 

 lated, sometimes confluent. The skin of the 

 fruit is killed on the space oeeu])ied by these 

 spots and ends in being replaceil by a layer of 

 cork. When the apple is invaded early the 

 skin may be killed over a large surface. The 

 latter not being able to keep up with the 

 growth of the flesh of the fruit, it follows that 

 the apple grows irregularly and that it forms 

 hollows more or less deep under the diseased 



