78 



MISSOURI BOTANICAL GARDEN. 



i 



from 



112/* 



d the nuclei found in them 



while some of the larger spherical ones are only 16 to 20/x, 



mea 



At 



growth and almost fills the entire host cell; a condition 

 which may be comparable to that found by Magnus (22) in 

 Neottia. It is likewise at this stage that the host nucleus ac- 

 quires its greatest volume; the cytoplasm filling every possi- 

 ble space in the cell which is not occupied by the fungus 

 19). The symbiotic relationship is now very evident, 

 e host and its guest seeming to prosper for a definite 



period. 

 Folio 



wing 



my 



the ends of 



fungal 



branches begin to swell, forming spherical or pear-shaped 

 bodies which much resemble the fruiting sporanges of a 



some 



small 



led by 

 being 



mycelium 



borne 



threads are so delicate 



tures break off very readily (f. 19, 20, 21). The young vesi- 



asm 



and dark staining bodies may be found (f. 20, 21), and later 

 the content segments into halves, quarters and even smaller 

 portions, in many of which a small nucleus may be deter- 

 mined. This process is quite analogous to spore formation 

 among higher types of fungi, yet no stage can be found where 

 there is a definite rounding up of the spore-like mass into 

 structures with definite w r alls. The formation of walls may 

 be inhibited because of the parasitic nature of the fungus, or 

 the fungus may be of that primitive type where no thick wall 

 is formed around the spore. 



It is at this stage that the host nucleus assumes an amoe- 

 boid shape, frequently becoming very irregular, and portions 

 project quite a distance into the fungal mass (f. 19, 25), a 

 condition probably due to lack of space in which to round 

 out more uniformly. This condition gives some indication 

 of the host cell assuming a digestive function although not 



