JOURNAL 
OF THE 
ROYAL MICROSCOPICAL SOCIETY. 
OCTOBER 1892. 
TRANSACTIONS OF THE SOCIETY. 
X . — Heterosporium asperatum ( Berk .) Mass., a Parasitic Fungus. 
By George Massee. 
{Read 19 th October , 1892.) 
Plate VIII. 
The above-named minute fungus has been under observation for the 
past four years, and all statements in connection with its development 
and mode of life have been corroborated by repeated cultures and 
experiments. 
It is a common and destructive parasite on the leaves of plants 
belonging to the order Liliaceas, and has been observed on plants 
EXPLANATION OF PLATE VIII. 
Fig. 1. — Heterosporium asperatum , on portion of a leaf of Smilacina stellata Desf., 
nat. size. 
„ la and 2. — Spores germinating in a sterilized solution of the host-plant 
(20 hours), x 500. 
„ 3. — Spores germinating in a solution of the host-plaut (48 hours) ; a, secondary 
spores ; 6 b, anastomosing hyphse. x 500, 
„ 4, 5. — Spores germinating in water (80 hours) ; a, secondary spores ; b, ana- 
stomosing hyphse; c, a hyphal branch that has formed a loop by curving 
and anastomosing with the parent hypha. X 500. 
„ 6. — Old sporophores that have produced secondary spores after remaining in 
water for four days ; a, secondary spores ; 6, sporophores. x 500. 
„ 7. — Spore germinating in a solution of leaf of sunflower ; a, sessile whorls of 
secondary spores, x 500. 
„ 8. — Spore germinating in water containing a trace of glycerin, x 500. 
„ 9. — A fascicle of sporophores bearing spores ; a, the sclerotioid base from 
which the sporophores spring ; b, a portion of the hyphse that produces 
the sclerotioid base, x 500. 
„ 10. — A stout hyphal branch running between the cells of the host-plant, and 
giving off slender branches that penetrate into the cells of the host. 
X 500. 
„ 11. — A stout, dark-coloured portion of mycelium growing in a dead leaf, and 
bearing two sclerotia. X 500. 
„ 12. — A sclerotium producing secondary spores in a solution of the dead leaves 
of the host-plant (80 hours), x 500. 
„ 13. — A pycnidium produced by stout, dark-coloured hyphse in a dead leaf of 
the host-plant, x 500. 
„ 14. — Section of a portion of the wall of a pycnidium, showing the origin of the 
pycnospores. x 500. 
2 R 
1892. 
