PANUS STYPTICUS LUMINESCENS 389 



been stuck with gum. The black letters, which were each 0-8 inch 

 high and collectively 2 inches wide, therefore pressed directly upon 

 the film of the photographic plate beneath. Upon the top of the 

 sheet of plain glass were then set about twenty Pa?m5 stypt. Iu7nines- 

 cens fruit-bodies with their strongly luminous under surfaces looking 

 directly downwards toward the letters and the film. To prevent 



Fig. 168. — A shadow-photograph of the black-paper letters of the word 

 Panus made with the light of about twenty small fruit-bodies of 

 Panus stypticus p.f. lurninescens gathered at Saint Paul, Minn., 

 U.S.A. The rectangular form of tlie liglited jjortion was due 

 to an inverted cardboard box which covered tlie fruit-bodies. 

 Exposure 15 hours. RejDroduced the original size. 



the fruit-bodies from drying up, they were covered over with a small, 

 inverted, lidless, cardboard box which was weighted above to keep 

 it in place. A good photograph of the letters was obtained with an 

 exposure of two hours, but the one shown in Fig. 168 was made with 

 an all-night exposure of fifteen hours. While the photograph was 

 being taken, the spores liberated by the twenty fruit-bodies formed 

 as many thick white spore-deposits upon the sheet of glass. 



By similar means to those just described was made the photo- 

 graph of the black paper star shown in Figure 169. On this occasion 

 about twelve fruit-bodies were employed, the fruit-bodies were 

 covered with an inverted crystallising dish, and the exposure was 



