20 
(’akne- tirnu'H Rot of Citrus. 
iophthora disoase in Western Australia, with the exeei^tion that 
lemons are stated to l)e appai'ently immune. Seville oran^es^ grape 
fruit, and eiinu|uats not investigated in Western Australia are also 
ittaeked. Tlie statement hy Cole that in an advanced state of this 
<lisease a stieky groAvtli develo])s on the fruit is probably <lue Wi 
eonfusion with tlie^ cominon se<-ondary Sour or Greasy IRot due to 
( > os po ra ci f ri-<i u ra u tii . 
Saniuers articles on Brown Hot in South Australia (26 27 1 
refer only to it attacking oranges. This disease as already stated 
is now known to he due to PtrytojOitJiom hihcrnoHs. Pythiaci/tis Thrown 
Hot in New” Zealand is recorded only on lemons (9) attacking tie 
fruit, leaves, laterals aiul even larger branches. Affected leaves 
turn brown, hut remain hanging on the trees. This disease appears 
to be distinct from that in Australia, and even from that in Cali- 
fornia. In South Africa, Brown Rot has been recently recorded only 
on orange fruits in AFarch and April, 1925, a year of exceptional 
rainfall (12). 
From the foregoing it. is evident that the disease in Victoria 
agrees in field symptoms more closely with the Western and South 
Australian disease than it does witli the Californian. Tn the absouc'' 
of any detailed mycologieal evidence to the contrary the writer 
considers that lie is justified in regarding all citrus Brown Rut in 
Australia as being due to P. hihernalis . 
ISOLATION OF PATHOGEN IN WESTERN AUSTRALIA. 
Jn September, 192.1, in conpiany with Dr. E. d. Butler, of th-‘ 
Imjierial Bureau of ^Mycology, and INFr. J. G. C. Cam])bell, a visit 
was made to an infected orchard fit Bicklev in the Darlinit Rano-e.s. 
The day was wet. 8j)ecimens of affected leaves and twigs shmving faint 
indications of superficial fungal growth were secured. Inuler micro- 
scopic examination these provi'd to be spore clusters of a Phycomy- 
cete. Previous to this date it w;is believed, following American 
(Experience with Ppthiaci/st is^ that the pathogen did not fruit on the 
trees. It ivas at once evident that the fungus diff'ered from Piithia- 
vjfstis. Over one hundred different successful atteinjits have been 
made during 192.1, 1924 find 1925 to develoj) the pathogen from 
diseased tissues in water, liijuid media or on agar. Tn every case 
the organism has been the same. Pi/thiarystis lias nevei' been 
found. 
Cultures have been submitted to Dr. E. J. Butler, Director 
the Imperifil Burcfiu of Mycology, who also isolated the same organ- 
ism in England in 1924 from West Australian oranges. He reporter! 
in 1925 that he was convinced that the organism was a new s[tecles 
distinct from Pyi hiacysfis. Cultures were also forwarded to M.a 
. E . M aterhouse, Sydney TAiiversity, who compared them with 
