90 



of infection to the stems. The principal features of its develop- 



and Karsten. 

 With the f 



am. Ward 



this the authors pay special attention. The tea plants which are 

 pruned between December and March show no marked sign of 

 disease till the end of March or April, but after the first heavy 

 rains of the season red patches suddenly appear on the young 

 wood. At the same time, or even earlier, the leaves will be 

 seen to lack vigour and to be suffering from chlorosis. The 

 red patches on the stem are due to numerous reproductive bodies 

 of the alga which burst through the bark, and probably represent, 

 as the authors suggest, the last stage of the parasite, infection 

 Having taken place the previous rainy season. 



Dealing with the spread of the disease, it is pointed out that 

 there are two methods by which the reproductive bodies may be 

 dispersed : (1) wind may convey the sporangia as a whole ; and 



\i r ! r :, m the forrn of rain or d <>w, may afford a medium for 

 tne distribution of the motile zoospores. The second alternative 

 excites no surprise, water being the natural vehicle for the spread 

 ot algal S po r es. Wind dispersion, on the other hand, may need 

 tunuer explanation. Oephaleuros possesses two types of repro- 

 ductive bodies, gametangia, usually more or less sunk in the 

 KW*' I zo °sporangia, which are elevated on sterile hairs. 

 « tnlt? 8nowe ^ that the zoosporangia (" haken-sporangia ") possess 

 doH^r mecban l sm which provides for their detachment, A 

 oLll ™-i n 3? cellul ose is formed at the junction of the stalk- 

 ed LTL B P ora ^m, splitting takes place at this ring which 



wTmrfo!lL.T ra ? g i Uin t0 be thrown off *• Mo. Dispersion by 

 or dew w i Bporangium, after being moistened by rain 



hi "hi v Sw t h Ut ;?K takes P lace b ? this m ^thod in Red Rust is 

 zoospores (^ >1 ?i bllt 1 t ^ account ^ iven of the germination of the 

 ^PX'tZ^^ 1 ^ — -3- before it will 



tuSSSo ffcST t 00 ?^*^ *M» reference to the passing of 



first ^S ( (VJ iZ t a n t0 l6af ' and < 2 > from leaf t0 8tem ' The 

 infection. The second - Wa * ent "-ely successful in producing 



not so decisive as could IT ^^ regarded as con ™ in S wa8 

 alga on the aitifi^tii w" e ° een wished ; the g rowth of the 



altogether chaiacteH s Ue A %*** \ 8h °° t8 bein ^ P 00r and n0t 



shoots from infectfrlffl Attem P ts to infect -■"— " 



rom mtected stems were without result. 



either leaves or 



is remarked that during the first 



year's growth the vrnmaT w» V ^marked that during the 

 hut this during the secon ?," P ° 88eS f a ron % h irr cgular stir 

 disease are found in th. 7 ?* 18 lmt Earl y stages of the 

 authors are of opinion tw C S Vlces of the young bark and the 

 arrowth t. ^LT nion tha t the rouirh snrfl «f\v, ««* ™ ar 's 



face, 

 the 



ough surface of the first year's 



Tl" r I Patches ;'iichann ed ^ the infecti ™ of the shoots, 

 represent the fruiting SaS^i. aft . er the ""** in A P"1 or May 

 of the previous year TtrL„ i , J nfecti on of the rough surface 

 the formation of visoron* ? health y shoots resist the disease by 



vigorous layers of bark, the al*a being thus 



