A NEW SPECIES OF MULBERRY FUNGUS. 195 



and their size. An allied fungus on the mulberry tree in South 

 Carolina, North America, was described by Prof. Berkely under the 

 name of Stereum moricolum ; and two other species of Sterevm^ viz. 

 S. suhcruentatum, B. et C. and .S'. contvariiim Berlc, are given in 

 Saccardo's Sylloge* These are Japanese species, but unfortunately 

 I have never yet found them. They must, however, be very distinct 

 from my species. For these reasons i venture to call it Helicohasidium 

 Mompaf from the well known Japanese name of the disease. 



The fungus at first attacks the root of a living tree, and the 

 diseased tree shows external symptoms of the disease on portions above 

 ground : usually the growth of shoots is arrested, the newly develop- 

 ed leaves become gradually smaller and at length die otf ; then the 

 lower part of the shoots begins to die, though the bark higher up 

 may preserve its normal appearance. It takes a tree one or two 

 months to reach this state, after it has first shown the external symp- 

 toms of the disease. 



On uprooting a young mulberry tree badly attacked by the 

 fungus, the roots are found to be killed from below upwards, and 

 present the appearance represented in Plate XXIV, Fig. I. The 

 tree figured there is three years old ; the roots marked a have grown 

 three years, and those marked h and c are of this year. The 

 portions marked a' are dead roots, whose bark was already severely 

 injured and so loose that it was separated by the act of uprooting. 

 As these dead roots were of no use to the tree, it produced the new roots 

 h to absorb nourishment from the soil. But the newly formed roots 

 were also injured as the disease advanced, and became unfit to per- 

 form their function ,• and at length another crop of newer roots c was 

 produced higher up, by means of which the tree was enabled to 



* Vol. IV. pp. 507 and 579. 

 t See p. 193. 



