388 RESEARCHES ON FUNGI 



containing the photogen are killed, great chemical confusion must 

 result. Various substances kept isolated from one another in 

 the living protoplasm rush together, and doubtless some of the 

 numerous chemical reactions and physical changes that go on are 

 fatal to the photogen. 



The spores are non-luminous. I examined dense fresh spore- 

 deposits which had been moistened with water or an agar nutrient 

 solution, but could not perceive that any light ever came from them. 

 This is in accord with the experience of Tulasne^ with dense spore- 

 deposits of Pleurotus olearius and of Kawamura^ with the spores 

 of Pleurotus japonicus. 



It is worthy of note that, whereas the spores of luminous fungi 

 are non-luminous, the eggs of certain luminous animals, e.g. Glow- 

 worms (Lampyris), emit light whilst they are in the ovary and after 

 being laid.^ According to the theory of symbiosis already mentioned,* 

 the luminescence of these eggs is due to their containing luminous 

 bacteria. 



Photographs made with the Light of the Gills. — To obtain 

 photographs made with the light of Panas stypf. luminescens I 

 proceeded as follows, my method being identical with that used 

 by Kawamura for making photographs with the light of Pleurotus 

 japonicus. In the dark-room a rapid photographic quarter-plate ^ 

 was laid on a table with the film turned upwards. The plate was 

 then covered with a thin sheet of plain glass to the under surface 

 of which five black paper letters, making the word PANUS, had 



^ L. R. Tulasne, " Sur la phosphorescence spontanee de VAgaricus olearius DC, 

 etc.," Ann. d. sci. nat., s6r. 3, T. IX, 1848, pp. 338-364. 



- S. Kawamura, loc. cit., pp. 8-9. 



^ Cf. E. X. Harvey, loc. cit., -p. 11. F. H. Fabre in his book The Wonders of Instinct 

 (London, 1918, pp. 287-288) thus characteristically describes the bioluminescence 

 of the eggs of the Glowworm : " Here is a very singular thing ; the Glowworm's eggs 

 are luminous even when they are still contained within the mother's womb. If I 

 happen by accident to crush a female big with germs that have reached maturit}^ 

 a shiny streak runs along my fingers, as though I had broken some vessel filled with 

 a phosphorescent fluid. The lens shows me that I am \\Tong. The luminosity comes 

 from the cluster of eggs forced out of the ovary. Besides, as laying time approaches, 

 the phosphorescence of the eggs is already made manifest. ... A soft opalescent 

 light shines through the integument of the belly." 



* P. 380. 



^ Two kinds of plates were used: (1) Royal, special extra rapid, speed 180 

 Watkins and (2) Seed, R., speed 280 H.D. 



