50 



the presence of a dark, tear-like fluid whicli 

 issued from the affected parts. The disease, 

 which was not regarded as being very detrimen- 

 tal, was usually seen on older plants, more especi- 

 ally during seasons of low temperature. Sig. 

 Eagusa thought that the condition was due to a 

 root-malady, and was probably identical with 

 the "cancer" described by Buiso (1879, pp. 

 102-3) under the name of " Male di cancro." A 

 grower at La Favorita, near Palermo, used the 

 term " Male nero " for a similar, if not identi- 

 cal, disease whose presence was indicated by the 

 death and decay of individual joints or portions 

 of a joint, from the edges inwards, the alteration 

 being often accompanied by the exudation of 

 drops of dark, sticky material. Low tempera- 

 tures and rainy weather favoured the develop- 

 ment of the malady. The symptoms and effects 

 of this trouble are similar to those described as 

 occurring in Queensland (Tryon, 1908, p. 143; 

 1911, p. 6) in plants suffering from " dry rot," 

 a disease which is suggested as being due to un- 

 suitable soil conditions interfering with healthy 

 root action. It is not, however, a malady which 

 can be utilised in destroying prickly-pear in 

 Australia. 



Cancer. 



This disease, which has been referred to by 

 Biuso as Male di Cancro, by Savastano as Mar- 

 ciume, and by Sprenger as Erehs, was noticed 

 near Palermo. Affected plants were chlorosed, 

 showed no signs of growth, and possessed little 

 or no fruit. On being pushed it was observed 

 that there was a tendency to topple over, thus 

 indicating that root decay had set in. Those 

 which were attacked died, as also did those 

 planted to replace them, and the disease tended 

 to spread outwards from infected situations. An 

 examination of the roots and base of the stem 

 showed that there had occurred a decomposition 

 of the tissues between the woody structure and 

 the epidermis, these becoming translucent and 

 yellow, changing to dark brown. 



Although the affected plants of 0. ficus- 

 indica examined near Palermo did not present 

 general symptoms corresponding in all particu- 

 lars with those described as occurring in speci- 

 mens of the Queensland pest pear suffering from 

 " sleeping sickness " (Tryon, 1908, p. 143; 1911, 

 p. 7), there is little doubt that the two diseases 

 are the same, and are probably caused by a 

 root-destroying organism, which later unpub- 

 lished investigations indicate to be a species of 

 Pythium. 



Biuso (1879, pp. 102-3) has given an account 

 of a contagious malady which seems to be the 

 same disease as that just referred to. He men- 

 tions that the gangrene produced usually mani- 

 fests itself in the basal portion of the stem, gener- 

 ally in spring or autumn, as an alteration of the 

 woody tissues, extending gradually to the more 

 internal tissues, which decompose into a fetid 

 yellowish-green mass. 



The same malady is described by Savastano 

 (1897, p. 110) under the name " II marciume," 

 as occurring near Catanzaro (Calabria) and in 

 Sicily. An English summary has already been 

 published by one of the members of this Com- 

 mission (Tryon, 1908, p. 143; 1911, p. 15). It 

 is stated that the disease travels rapidly from 

 the roots along the vascular region of the trunk 

 and branches to the joints. Here the celliilar 



structures undergo alteration so as to become 

 translucent. Besides, there is a formation of 

 tubercles in groups along the course of the con- 

 ducting tissues, each tubercle being composed of 

 transparent cells surrounded by other cells with 

 thicker walls so as to form a capsule. No exter- 

 nal swellings are noticeable, however. The dis- 

 ease is regarded by Savastano as being due to a 

 bacillus, which on inoculation is capable of repro- 

 ducing the disease under certain conditions, but 

 it was found that healthy plants on inoculation 

 did not contract the malady. He did not regard 

 soil-water as a necessary agent for its transmis- 

 sion. 



Sprenger (1901, p. 78) has referred to a 

 disease under the name " Krebs," occurring in 

 South Italy, which is probably the same as that 

 referred to above. The rotting of the whole plant 

 is the result of its activity. 



Mr. Berger related the symptoms of a 

 disease formerly attacking prickly-pear plants, 

 9 or 10 years old, at La Mortola. It was prob- 

 ably the same malady as that just mentioned. 



Male di Verme. 



Insenga (1879) has given attention to a 

 disease which is known in Sicily under this name. 

 Biuso (1879, p. 101) states that it is locally be- 

 lieved to be due to the attacks of an unidentified 

 caterpillar — Whence the name given to the malady 

 — and that the appearance of affected plants 

 suggests the reasonableness of this idea. He goes 

 on to say that Insenga has proved it to be due 

 to a fungus which invades the joints and arrests 

 the activities of the conducting tissues, thus pro- 

 ducing chlorosis and other evidences of plant 

 starvation. 



Minor Diseases. 



Leaf Scah. — This disease is regarded as being 

 due to a fungus (Phyllosticta opuntia, Sacc. and 

 Speg.) , but it is suggested that this organism only 

 becomes established on injured areas. It is local 

 in its distribution on the plant and has very little 

 effect except when it covers a great portion of 

 the surface of the joints. Comes (1891, p. 53) ; 

 Voglino (1905), p. 232); Briosi and Cavara 

 (1890) ; and Sprenger (1901, p. 78) refer to it. 



This fungus is widely distributed through- 

 out the Mediterranean coasts, being commonly 

 seen on 0. hergeriana, in a plant now naturalised 

 in the Italian Riviera. A similar, if not identi- 

 cal, organism is met with on the pest pear in 

 Queensland. 



Phytophthora cactorum, Leb and Cohn, a 

 serious pest of Cactacese, especially young plants, 

 occurs in some European greenhouses, where it 

 causes a rotting that commonly ends in the death 

 of the infested host, the decay usually extending 

 upwards from the lower portions of the plant. 

 An account of the parasite, which was not met* 

 with by the Commission, is given by Hartig, by 

 Prillieux, and by Hirscht (1899, p. 795). P. cac- 

 torum is allied to many dangerous enemies of 

 economic plants, and its own attacks are not 

 restricted to the Cactaceaj. 



The black wart fungus, Diplodia opuntice, 

 Sacc, has been recorded as a parasite of cultivated 

 Opuntins in Europe. Cooke (1905, p. 125 ; 1906, 

 p. 168), in referring to the occurrence, mentioned 



