248 INTRODUCTION TO CRYPTOGAMIC BOTANY. 



240. Fungi, like Algje, for the most part exhibit merely dif- 

 ferent modifications of cellular tissue, but they do not, as at 

 present known, show the tendency which many Algae do, to 

 produce dotted cells ; that is, cells in which the walls are 

 pierced within a little distance of the extreme surface, in order 

 to render the transmission of fluid more easy. There are, 

 however, a few cases in which as undoubted vascular tissue is 

 produced as in any Phsenogam ; as, for example, in the 

 capillitium of Trichia and Batarrea (Fig. 5), where the 

 tissue performs the same part as the elaters of Junger- 

 Tnannia. It is, however, far from common in the Myxogastres, 

 and is wholly deficient in the closely alHed genus Arcyria. 

 It is very doubtful whether in either case it performs any office 

 of aeration similar to that which obtains in Pheenogams. 



241. One of the most curious cases of the formation of 

 analogues of spiral cells is that reported by Bary,* in the case 

 of the transformation of portions of the mycelium of Asper- 

 gillus glaucus into the sporangia of Eurotium. Either two 

 contiguous branchlets, or a portion of the centre of a thread 

 are twisted round so as to form a body shaped like the 

 nucule of a Chara, but at first hollow within. The spirals 

 after a time become incorporated, cells are generated from 

 them, the cavity is filled with protoplasm, and ultimately asci 

 are formed filled with spores, which, like those of the mopshaped 

 heads, are capable of germination. I have had no opportunity 

 of examining the matter myself, and therefore simply report 

 the statement of Bary. He does not himself profess to have 

 observed every intermediate stage. 



242. The cellular tissue varies in almost every conceivable 

 way, both as regards form and composition. Cells occur per- 

 fectly globose, and also extremely elongated and attenuated ; 

 and in some instances, as in Vaucheria (Fig. 22), not a single 

 dissepiment is formed (Fig. 23) from the first germination of 

 the spore till impregnation, so that the whole plant is a 

 single ramified cell, whose apices fall off and reproduce the 

 species. By a combination of differently formed cells, whose 



"■ Bot. Zeit., V. 12, p. 425. 



