98 RESEARCHES ON FUNGI 



between the cells in trichogynes was observed : by Baur 1 (1898) in 

 Collema crispum ; by Darbyshire 2 (1900) in Physcia pulverulenta ; 

 and by Kienitz-Gerloff 3 (1902) in Collema. 



In the summer of 1932, Mr. S. P. Wiltshire of the Imperial 

 Mycological Institute, Kew, showed me central pores in the septa of 

 multiseptate spores of Stemphylium paxianum (v. Szabo) Lindau 

 (Baarn culture) and of Alternaria circinans (B.et C.) Bolle, mounted 

 in lactic acid (Fig. 53). These pores could readily be seen in the 

 middle of obliquely situated septa as rounded apertures through 

 which light passed more freely than through the dark wall-sub- 

 stance. Doubtless, when the spores were living, protoplasmic 



strands passed through these 

 pores and thus united the whole 

 of the protoplasm of each spore 

 into a single mass. 



In the autumn of 1932, with 

 the help of Dr. E. S. Dowding, 

 Fig. 53.— Central open pores in the I succeeded with the iodine and 



middle of the septa of multiseptate chlor . zinc iodine me thod in ob- 

 spores : to the left, btempnylium 



paxianum; to the right, Alternaria serving quite clearly the proto- 

 circinans. Drawn by S. P. Wilt- . . 



shire. Magnification, lioo. plasmic bridges passing through 



the septa in mycelial hyphae of 

 Fimetaria fimicola and of Rhizoctonia solani (= Corticium solani). 

 Drawings illustrating these bridges are reproduced in Fig. 54. 

 Attempts to see the bridges in the inner stipe cells of Psalliota 

 campestris and in the mycelium of Coprinus sterquilinus failed to 

 give conclusive results, as the protoplasm, in consequence of im- 

 perfect fixation, usually became much contracted. 



In the spring of 1933, Dr. P. H. Gregory, at my suggestion, 

 sought for pores in the septa of certain dermatomycetes obtained 

 from ring-worm patients at Winnipeg. With the help of the iodine 

 and chlor-zinc iodine technique he had no difficulty in finding the 



1 E. Baur, " Zur Frage nach der Sexualitat der Collemaceen," Ber. d. D. hot. 

 Oesell, Bd. XVI, 1898, p. 366. 



2 0. V. Darbyshire, " Uber die Apothecienentwicklung der Flechte Physcia 

 pulverulenta," Jahrb.f. wiss. Bot., Bd. XXXIV, 1900, p. 336. 



3 F. Kienitz-Gerloff, loc. cit., pp. 105-106. 



