230 BOTANICAL GAZETTE [September 



excellent field for investigation. Matre 27 has described the organs 

 of absorption of Asterina usterii and Asterina typhospora. A 

 slender filament penetrates the epidermal wall and when it has 

 reached the cavity of the cell it enlarges and becomes profusely 

 branched. 



The opened perithecia of the rose fungus present characters 

 indicative of a close relationship to the Phacidiales. The ragged 

 margin of the shield suggests the ruptured outer portion of the 

 wall of the fruit body which at first covers the hymenium. The 

 presence of knobbed paraphyses is also a character possessed by 

 many Discomycetes. In the Phacidiales, however, as far as can 

 be learned, the upper or outer part of the fruit body is not separate 

 in origin from the ascogenous stroma, nor does it possess the 

 characteristic structure, of the shield present in the Microthy- 

 riaceae. On the other hand, it is quite probable that few of the 

 Microthyriaceae possess a stroma within the leaf tissue as has been 

 described for the fungus in question. The majority are apparently 

 superficial and with a well developed wall or shield only on the 

 upper side. In spite of these facts, I feel that this fungus should 

 be placed in the Microthyriaceae. Further morphological study 

 of other species of this genus and related genera will throw some 

 light on the relationship of these microthyriaceous forms. Perhaps 

 the systematic position of many of these forms will be changed 

 as soon as the species have been satisfactorily investigated. While 

 the possession of the shield and the hyaline 2-celled spores are 

 characteristics which would suggest the position of the rose fungus 

 in the genus Asterella, yet, as has been pointed out, this genus is 

 not clearly limited and contains heterogeneous elements. This 

 fungus does not seem to accord morphologically with the members 

 of this genus in the sense in which the genus was first employed. 

 Species representing several generic types apparently have been 

 included in Asterella. Since the characters presented by this 

 fungus are evidently those of a distinct generic type, rather than 

 place it in the genus Asterella, it seems better to treat it as the type 

 of a new genus. Because of the two separate structures, the shield 



2 7Maire, R., Les Su^oirs des Meliola et des Asterina. Ann. Myc. 6:124-128. 

 fig. 4. 1908. 



