46 H. MARSHALL WARD. 



gated to form the long neck of the perithecium. It thus comes about 

 that the free apex of the ripe peritheciurn corresponds to what was 

 the attached end of the ascogonium. 



The walls meanwhile become coloured deep brown, and rudimentary 

 paraphyses spring from their internal layers. The asci arise from the 

 colourless cells of the ascogenous core, in which a cavity is produced 

 by the tangential growth of its peripheral cells. 



In the concluding remarks stress is again laid upon the fact that 

 we cannot speak of an antheridium here ; the antheridia have degene- 

 rated to mere vegetative hyphce, and the ascogenous core produces its 

 asci without any sexual process whatever. A single cell produces the 

 asci. In most respects this agrees with Gilkinet's description of the 

 analogous processes in Sordaria fimicola. 1 But in Sordaria, Gilkinet 

 finds one enveloping hypha apply itself to the ascogonium before the 

 rest, though he could not decide that copulation took place. 2 Kihl- 

 mann denies that this can be termed an " antheridium." He regards 

 Melanospora as somewhat midway between those Erysiphece which, 

 like Eurotium and Podosphcera, have the sexual organs at least mor- 

 phologically present, and the truly apogamous Pyrenomycetes, Chceto- 

 mium 3 and Pleospora. i We may no doubt fairly represent these views 

 in such a diagram as the following : 



Pleospora, &c. (completely apogamous) 



Melanospora (no antheridium) 



Podospluera (sexual organs well developed). 



I now proceed to notice a further contribution to our knowledge of 

 the Ascomycetes, by Eidam. 5 Passing over his description of Ere- 

 mascus albus, a new species and genus (in which the process of con- 

 jugation is, however, strongly suggestive of the Zygosporece), we may 

 briefly notice the general absence of any recognisable process of fertili- 

 sation, though an ascogonium is always present, and Eidam seems to 

 regard one of the enveloping branches as an antheridium — morpho- 

 logically at least. 



This observer has studied the development of the perithecium in 



1 ' Bull. Acad. r. de Belgique,' ser. 2, t. xxxvii. 



2 Cf. also De Bary and Woronin, ' Beitr. zur Morpli. und Phys. der Pilze, &c.,' 1870, R. iii 

 8 Zopf, ' Nova Acta, Leop. Car. Akad.,' B. xlii. 



1 Bauke, ' Bot. Zeit.,' 1877. 



6 Cohn's ' Beitr, zur Biologie, &c.,' B. iii, H. iii. 



