Minnesota Plant Diseases. 169 



and bore cross walls. Externally, therefore, the Jews' ear and 

 trembling fungi and also the following group may be very simi- 

 lar and indistinguishable to the naked eye, but the microscope 

 shows a difiference in the structure of the basidium. Similar 

 accessory spore-forms are also produced in the trembling fungi 

 and a very considerable variety of such forms is found. The 

 trembling fungi are very common in our woods, growing on 

 dead sticks and logs, especially after heavy rains. After shed- 

 ding their spores they usually hquify under the action of bac- 

 teria and other organisms, for they furnish good media for 

 these plants. When dried the trembling fungi become hard 

 and horn-like, resuming their gelatinous nature when again 

 placed in water. 



One of our common forms resembles a brownish, irregular 

 or shelf-like mass of gelatine and is commonly known as 

 witches'-butter. The brain-like forms are also very common, 

 often producing masses weighing five pounds. Toothed forms 

 have been found in several places in the state but are seldom 

 abundant. These toothed forms are not unlike the true 

 toothed fungi in appearance but are always more or less gelatin- 

 ous. Economically this group of fungi is not important, 

 though they may aid in timber rotting to a slight extent and a 

 few forms have been pronounced edible. One very common 

 form is tough and leathery and resembles greatly a much- 

 branched club fungus. (Figs. 78, 80.) 



Weeping fungi {Dacryomycetinece). These fungi include an- 

 other group of gelatinous fungi similar in apparent characters 

 to the two previous groups. There is again a variety of shapes 

 produced, but our commoner forms are irregularly club-shaped 

 or brain-like. The basidia are again arranged in palisade-like 

 areas at the surface of the fruiting bodies, but these basidia are 

 single-celled, having no walls dividing them into several cells. 

 The basidia are fork-like in form and each of the two tines of 

 the fork bears at that end which comes to the surface of the 

 gelatine a single spore. Accessory spores are also produced. 

 The most common Minnesota form is one, which is abundant 

 on fallen logs and stumps of larch and other soft woods. It is 

 at first bright orange, but soon after the shedding of the spores 

 the fruiting body liquifies, whence its common name of weeping 

 fungus. 



