Lecture II 



— 27 — 



Occurrence of Mycorrhizae 



The genus Cupressus has attracted no modern investigator except 

 that Birch (1937) says that in New Zealand the fungus Rhisopogon 

 rubescens appears to be a mycorrhizal symbiont of C. macrocarpa. For 

 the Italian cypress, C. sempervirens, mycorrhizae were described by 

 Janse and by Kirchner (1908), the former describing necklace- 

 beads and the latter simple coralloid mycorrhizae with endotrophic 

 mycelium. Berggren (1887) had stated that Hartig net is lacking; 



Fig. 2. — Mycorrhizae in Pinus virginiana. A 

 "long-root" is beset with mycorrhizal short-roots 

 or mycorrhizae, which in the older portion exhibit 

 beginning of coral branching by dichotomy. The 

 mycorrhizal sheath or mycoclene over the apex has 

 split by renewed growth. 



Yeates (1924) that the fungus is similar to that in Taxads. One 

 other species, C. Lindleyi, was reported to have no root hairs by 

 SCHWARZ (1883). 



Chamaecyparis is even less studied than Cupressus, having no 

 modern investigator except that Kle5ka and Vukolov (1935) list 

 C. Lawsoniana as having endotrophic mycorrhizae. Noelle (1910) 



