4UU INSECTICIDES, FUXdlCIDES, AND WEED KILLERS. 



curs hitween these two new t'ovius aiicl the 

 female lays iu aiituiun the siii,<,'le egg re- 

 I'erreil to al)Dve. It will thus he seen with 

 what rapiility a hot-heil of i)hylloxera may 

 extend ami propagate itself in the neigh l)anr- 

 hooil. In the south of Fvanee the phylloxera 

 Urst appeared about 1863. In 186.'t a real 

 invasion was reported near Avignon and at 

 Floriac, near Bordeaux, wliirli spread rai)iillv. 

 It was not until LS«S that l'lanrlH>n di's- 

 .■ n-rrrd thcrans- of thcM' rava-v-, thr l'h,,l. 



known in\\nu'rwa uiI'h-r''iN' v." ';--''.' Inrni 

 sine.- Lsr.l and in (Jrcat Hrit.iin wli.iv it ap- 

 peared in the greenhouses as far baek as 

 1863. Iu 1877 itinvadeil the department of 

 Loir ami Cher, where iu the first year it de- 

 strovrd I'ssjiDO hectares of vines (720,000 

 a ivsi: in ls^^, 429,000 heetares (1,072,.500 

 a' I'csi sliared the same fate, and in 1888 half 

 of all the French viuev:n'ds wen- invadcl or 

 destroyed by this fofniidalilc parasite, hi 

 that way the crop diminisheil eon^i.leral'ly : 

 in Vaueluse, for example, it fell in 1,>76 

 tr.ini 100,000-.500,000 hectolitres (8,800,000- 

 11,OIJO,000 gallons) to 49,000 hectolitres 

 (1,078,000 gallons). It was only from the 

 be.tjinning of that time, that is in 1874 and 

 1S76, that the phylloxera reached Germany 

 and Switzerlaml. Energetic measures were 

 taken to prevent the propagation of this 

 insect, and the importation of vines from 

 eontaminated countries was prohibited. 



FlERis Brassice. Pierin Rajje (large 

 white cabbage butterfly, small white cab- 

 l)age butterfly).— They are white, diurnal, 

 well-known butterflies. The former female 

 lays its eggs iu June on the surface of the 

 cabbage leaves where these masses form 

 plates of a white colour ; the f.:;male of the 

 second lays its separate eggs in packets. The 

 caterpillars of the former are greenish-grey 

 with three longitudinal lines and reaeh ;-, 

 centimetres in lenutli ; that nftlie see, md are 

 green with three yellow lon-iludinal stripes. 

 There are two generations a year. Tlfe cater- 

 pillars attack all crueiferaj ; they are danger- 

 ous because they appear iu very large numbers 

 and gnaw tlie leaves, leaving oidy the veius. 



FissoDES NOTATUs (small pine weevil). — 

 A smaller-sized weevil than the large pine 

 weevil, S niillinietreslong, brownish-red with 

 el>tra sti'i|i -I witli two whitish cross bands. 

 It at I I k. |,ni.- plantations of four to eight 

 yi-ars whi. li it devours in the adult as well 

 as in the larva state. The perfect insect, 

 which appears in May, gnaws the terminal 

 shoots and buils, especially those of the 

 /'ill IIS ,s///r s///v or of the Weymouth pine. 

 'I'lie teniale kavs its eggs in the liark of the 

 iiiuh parts (if the tree. The larvffi bore 

 sinuous holes between the wood and the 

 bark ; they turn into grubs in these holes. 



Plasmodiophora Brassic.b (Anbury, 

 finger and toe). — This disease is charac- 

 terized by excrescences on the roots. It 

 causes stoppage of growth and kills the 

 plant. This disease may attack all varieties 

 of cabbage, as well as beets, turnips, and 

 radishes. The fungus which accompanies 



this disease belongs to the family of .Myxo- 

 mycetes, fungus consisthig of a protoplasmic 

 mass, the plasmodium, which changes in- 

 cessantly in shape and which moves after 

 the style of the lower organisms, the amoeba. 

 POLYPORA. — These receptacle fungi form 

 projecting lamclhe either fleshy or ligneous 

 in the form of a bracket or a horse-shoe 

 attached laterally by their base in the in- 

 terior of which their mycelium is spread. 

 Polypores attack fruit trees. Tliey cause 

 white rot esp-cially of the wood of the oak. 

 They rapidly damage the wood of the trees 

 which they invaile. Tiie infection occurs 

 especially in the spots where there are 

 fissures which have been produced by frost, 

 where there are sections of cut branches, in 

 short all wounds are open roads to the pene- 

 tration of these dangerous fungi. 



PoLYPORUS lUNlARias (false tinder 

 fungus). — As widespread as P. sidphnrens, 

 it preferably attacks very old oaks and there 

 causes white rot, but it also shows itself on 

 the beech, the poplar, the hornbeam, the 

 willow, and on fruit trees. Infection is pro- 

 pagated by passuig from the alburnum and 

 the liber to the heart-wood. The latter is 

 rapidly consumed, ijissolved, and reduced 

 into a whitish friable mass which is separ 

 ated from healthy wood by a brown border. 

 The receptacles are ligneous caps, rust- 

 brown and greyish colour ; flocked on the 

 upper surface they rise one above the other. 

 Poi.vrimrs sri,riiiKi:rs(heart wood rot). 

 —This widespread tiumns especiallv attacks 

 the oak, tlie walnut, tin- jicar-tree," and the 

 poplar. Where it fructilies yellow sulphur- 

 ous hoods appear rising one above another. 



POLYSTIGMA RUHRUM (plum-leaf blister). 

 —In the spring the leaves attacked by this 

 fungus are , nvei-ed on the two faces by red 

 spots eiiri-e>|j inding to small receptacles of 

 spores formeil on the mycelium which de- 

 velops in the middle of the parenchyma. 

 By developing between the cells of the 

 tissues, this mycelium separates the cells 

 from one another and disorganizes the 

 tissues that cause the exhaustion and 

 weakening of the tree. The dead leaves 

 contain peritheca, which jiroiluce s])ores in 

 February or March. Tlu'se spores jilaecd on 

 a leaf of the plum-tree gernunate in a few 

 hours, and their germination tube perforates 

 the epidermis to penetrate into the paren- 

 chyma of the leaf. 



Potato Disease. Phytnphthora infest- 

 ft?i.9.— The fungus which is the cause of this 

 disease attacks the leaves, the stems, and 

 the tubers of the potato. The disease ap- 

 pears first on the leaves and the stems where 

 it shows as brown spots which end by cTitirely 

 covering them. In wet weatlier it spreads 

 rapidly and may then destroy the plant. 

 The disease develops likewise in the tubers 

 where it shows itself by brown spots and by 

 an alteration of the adjacent tissue. The 

 infection of the tubers is not always induced 

 by the mycelium of the aerial part of the 

 plant, the latter only penetrating rarely 

 down the stems into the tubers. The tubers 



