352 J. G. WALLER ON PARASITIC VEGETABLE ORGANISMS. 



throughout, and giving some colour by its prevalence. PI. XIV ., 

 Fig. 6, shows a small particle, about the 25th of an inch in diameter? 

 which gives a good idea of the general appearance of the organism 

 not unduly developed. The large globular bodies I shall refer to 

 presently. At Fig. 7, is another specimen, in which the delicate 

 mycelium is more seen, as well as other characteristics not unfre- 

 quent, in which there is confluence of parts without determinate 

 form. Selecting an individual plant will now instruct us in details 

 (Fig. 8). At the aperture (a) we see where the first beginning 

 took place, often shown by a small mass of granular matter, thence it 

 descended into the shell, developing itself with conidia or buds from 

 its sides, and proceeding in an irregular succession of bulbous ex- 

 pansions. A filamentous mycelium grows from one of the conidia, 

 then a narrow neck ends in the perithecium, which, opening out on 

 the surface of the shell, disperses its spores. 



This example gives the plant in its simplest condition, and so far 

 explains its character. But its growth is most irregular. Some- 

 times it proceeds by a straight filament of similar diameter through- 

 out, at others it is always altering its shape, and no precise defini- 

 tion can be given to it. When decalcified it is extremely brittle, 

 and in mounting a specimen it broke up on mere pressure of the glass 

 cover. Thus, some matters of detail became more easy of investi- 

 gation. A group of connected bulb-like forms are here figured (Fig. 

 11), and a perithecium is shown in a side-view (Fig. 10). In 

 another example the latter is found in a perfect condition before the 

 spores are dispersed, and exhibits a transparent hyaline operculum ; 

 but the conditions under which it was seen prevented the use of high 

 powers. 



One specimen still further illustrates the reproductive mode by 

 conidia, and showing several conditions (Fig. 9), and this is so like 

 that given in figures of Saprolegnia ferax, that it helps us in our 

 argument, which would place the latter amongst the Fungi, where 

 hitherto the ground has been debatable. For if we assume the rest 

 of these organisms to be so classed, we can scarcely omit this, and if 

 I am right in assigning the plant I am describing to the Saprolegnia, 

 by the same reasoning the place of that genus would be defined ac- 

 cordingly. 



But this important example must be examined in detail, as it 

 exhibits many gemmae or conidia, using these terms according to 

 the views of Tulasne, in different conditions of development. Of 



