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The above described interesting fungus, which Hves, probably as a 

 parasite, on the pinnae of Trichomanes pinnatum, was collected in the 

 Maravalh-valley in Trinidad by H. Lassen. Unfortunately the material 

 is very scarce, as upon the whole only a few stromata are at hand. 



The small, in alcohol greyish, stromata seem at first sight to be 

 hypocreaceous ; in drying up they collapse and thereby disclose their deli- 

 cate, membranaceous structure. Under the microscope they are seen (in 

 vertical section) to be composed of a very thinwalled, small-celled, some- 

 what indistinct parenchyma, in which the asci come into view. In the 

 sterile margin (and on the surface) the stroma appears somewhat bys- 

 soideous and as a rule the single hyphae can be distinguished; they are 

 often uneven owing to very short branches, which project under a right 

 angle. In many cases we have observed that these peripheral hyphae 

 seize upon coccoidal algae (6 — 7/y. long.), the relation between the fungus 

 and these algae however being of so superficial and fortuitous a character 

 that there is by no means to be thought of a lichenisation (fig. 2 b). In 

 the inner of the stroma appear a number of ascigerous cavities, each 

 containing a single ascus; most frequently the asci are placed in 1—2 

 layers, as shows the fig. 2cr. The young asci are as a rule lying on a 

 lower level and are encircled by a very thick gelatinous membrane; on 

 increasing they distend the surrounding tissues and thereby approach to 

 the surface of the stroma; the full-ripe ascus has a diameter almost 

 equal to the height of the stroma and is provided with a gelatinous membrane, 

 which, seen from above, appears as a conspicuous, light-refracling circle 

 around the ascus. The liberation of the spores takes place by liquefac- 

 tion of the asci and destruction of the upper part of the stroma; the 

 tissues over the full-ripe ascus often project a little from the level of the 

 surface of the stroma. There is no parietal layer around the single cavities, 

 which however persist even when the asci are prepared out. 



Owing partly to the great difference between the structure of the 

 fungus and that of its substratum, partly to the fact that the single stro- 

 mata are rather losely affixed to the surface of the leaf we did not succeed 

 in cutting good microtome-sections of the material; the nuclei however 

 appearing distinct in the stained sections we observed in the young asci 

 a very great nucleus. Far better results were obtained by cutting the 

 material, enclosed in cork, with a razor, or by gently smashing the single 

 stromata under the microscope. By this latter method we happened to 

 establish that the asci arise terminally on hyphae, which in a number of 

 7 — 10 ( — more) go out from a common starting-point (fig. 2 c). The 

 walls of these ascogeneous hyphae, the length of which surpasses the 

 diameter of the ascus twice or more, likewise deliquesce at an early 

 stage, owing to which the proximal parts of the hyphae easily disappear, 



