HOTSON. — CULTURE STUDIES OF FUNGI. 231 



the use of a number of papers belonging to his private library; to 

 Professor Elias J. Durand of the State University of Missouri, for 

 the description and naming of Cnhonia bulbifera; to Professor W. G. 

 Farlow for material and the use of several articles from his private 

 library. 



Review of Literature. 



The literature relating to bulbils is, as has been already indicated, 

 by no means extensive, and deals with less than a dozen described 

 forms, some of which do not appear to have been recognized by 

 mycologists since their original publication. In order to give a 

 clearer idea of the present state of our knowledge of the subject, it 

 seems desirable, before proceeding further, to give a brief summary 

 of the more important papers, which may be conveniently considered 

 seriatum under the following heads: 



(a) Helicosporangium, (b) Papulospora, (c) P^^renomycetous 

 Forms, (d) Discomycetous Forms, and (e) Basidiomycetous Forms. 



(a) Helicosporangium. 



The genus Helicosporangium was first described by Karsten ('65) 

 and was based on a form said to be "parasitic" on beet roots, 

 which he named H. yarasiticum. According to his description the 

 fertile branches of this fungus tend to become erect, and are septate 

 like the rest of the hyphae. In the process of development they coil 

 up spirally at the end to form the bulbil. This character suggested 

 that they might be closely related to such hyphomycetous forms as 

 Helicoma Corda, Helicosporium Nees, Helicomyces Lk., Helico- 

 trichum Nees, etc. In fact, it was this spiral development of the 

 fructification, held in common with these forms, that suggested to 

 Karsten the name, Helicosporangium. 



At maturity these bulbils are described as almost spherical, with 

 one large central cell which is surrounded by a single layer of colorless 

 cortical cells which form a complete wall. Karsten believed that one 

 of these cortical cells produced a short protuberance on the inner side, 

 which extended into the large central cell, in which he says a "nu- 

 cleus" soon appeared and enlarged quite rapidly. He further ob- 

 served that the contents of the central cell soon became somewhat 

 differentiated and divided into a number of small cells, usually eight 

 in number, but varying from seven to ten, which gradually enlarged 

 to form free, hyaline, elliptical spores; and, after escaping from the 



