RESEARCHES ON FUNGI 



CHAPTER I 



THE FORMATION OF HYPHAL FUSIONS IN THE 

 MYCELIUM OF THE HIGHER FUNGI 



Introduction — Investigations by the Author — Methods and Materials — A Generalisa- 

 tion on Hyphal Fusions — The Four Kinds of Hyphal Fusions — Hypha-to-Hypha 

 Fusions — Hypha-to-Peg Fusions — Peg-to-Peg Fusions — Hook-to-Peg or Clamp- 

 connexion Fusions — The Function of a Clamp-connexion — Clamp-connexions 

 and the Hooks of Ascogenous Hyphae — Biological Significance of the Hook of a 

 Clamp-connexion growing Backwards instead of Forwards — Mile Bensaude's 

 Second Mode of Formation of a Clamp-connexion unconfirmed — Pleurage 

 curvicolla — Pleurage anserina — Fimelaria fimicola — Pyronenui confluens — 

 Coprin us sterquilinus — Coprinus lagopus — Sphaerobolus steUatus — Microsporon 

 audouini — Critical Remarks on Supposed End-to-Side and Side-to-Side Fusions 

 — Action at a Distance in Vegetative Hyphal Fusions and its Theoretical 

 Explanation — Passage of Nuclei through Hyphal Fusions. 



Introduction. — It is well known that, in many species of Ascomy- 

 cetes, Basidiomycetes, and Fungi Imperfect i, the mycelium, owing 

 to the formation of numerous anastomoses between neighbouring 

 hyphae, becomes converted in an early state of its development 

 into a three-dimensional network. 1 In Volume IV of this work it 

 was shown that these anastomoses — there called hyphal fusions — 

 are of considerable functional importance. Thus, in the Hymeno- 

 mycetes, hyphal anastomoses make possible sexual co-operation, 

 facilitate the passage of nuclei through a haploid mycelium whilst 

 it is becoming diploidised, aid the flow of food materials to fruit- 

 bodies and sclerotia whilst these are developing, diminish the 

 deleterious effects of small wounds in a mycelium and, in any one 



1 Cf. these Researches, Vol. IV, 1931, pp. 152-180. 

 vol. v. n 



