'252 



h CO.M'KliKNCK IMi:i;\\ll()N\l,r, liK i;K.\KTI(II !•; 



possessa liigh dei^rco oT ailaplalion lo llic parasilic cxislcncc. and are.not loI)e 

 classofl with wcakliiiic or woutui parasites. 



I. Tlicv |i('Mi-li-a|p iii;ai(lc(l llie roots of llic liost. 



1'. 'l'Iirv l;i'ii\\ llirii (lie livinii: cpHs oT pool and st(Mii wilhoiil killinti l)y loxin 

 l'ormation Uic lissucs Ihcy inxadi-. (lonlrast lin- lii'liavidr nf Srlcdiiniu srlcrn- 

 tioruiii in ils alla<d< mi Irilucc. 



1. Kirlil ol' ri'sl-.|.iiil iiilicin. vMi'iely Hillnii, un smuic Ii.iiIIv iiilfcli'il I.-iikI :is preceiling picliirc. 



Fi};'. 3. — (lli,iiM|i (le i-dlon d'iiiio v:iri(''lc vi'sislaiili' " Dilloii "' sur lo môme lerrnin infesté 



(|iio criiii iiiiiiiliV' |i.ir l;i liiiui'e prci-i'ileiiN^ 



T>. Tliey ai'C hif^hlN ; pcciali/cd in llicii- adaplalion lu iic)>ls. Su l'ar as our 

 knowledtfc i^oos, / iisariiini nirc/nn allacks no olliiM' livint;- piani llian llic 

 walernielon. /•'. Irac/ieip/iHiiin oïdy llie cowpea (Vit/na) and /•'. vasinferli/m only 

 collon and ils roialive. okra {llihisru^ esciilenlufi). In this respect, coiipled 

 \vith tlieir ( Jose niorpliological resemljlanco and liieir coninion geographical 

 distrilintioii, tlicv seiMU to lie analog-ous lo llie Idoloiç-ical sirains of P/^rr//!/V( nnd 

 /•.V.vs/y;/,,.. 



i. Tlic iiiisl plants are allarkcd wlirn ollicrw i>i' licaitliy and tirowiny in 

 soi!. \vlii(di, ]iie\ious lo ils inlVclion li\ lliis Inni^us, was idéal l'or llieir besl 

 developmenl. i'Iie disi'ase uecurs in lields llial are neither loo dry nor loo 

 wel. FnrlIuM-niore. neil lier nei;leel of rultival ion noi-po\crt\ of soi! jtredispose 

 lo lliese diseasrs. If an\lliint>. will is worse on iiii;ldv cnilivaled and well 

 ferlili/cil lieliU. 



."), The occiii iciii-e anil niann<'r of spre;id in llu' lielil indieale lliat Ihe 



