2o8 DIVISION II. — COURSE OF DEVELOPMENT OF FUNGI. 



longer in the surface-direction, while the rind covering it does not grow correspond- 

 ingly, and the rind is therefore ruptured above the hymcnium, which is thus exposed 

 as a discus. 



Up to the time of the inception of the hymcnium beneath the rind no 

 changes of importance take place in the ascogonium. But now all its cells except 

 one are seen to become thick-walled and poor in protoplasm, and in this state they 

 continue permanently ; but that one cell, the third or fourth uppermost cell, becomes the 

 initial cell of the formation of asci, the ascogenous cell. It is full of protoplasm and 

 swells considerably, and then sends out twelve or more strong cylindrical branches from 

 its free outer surface. These are the ascus-forming branches, the ascogenous hyphae, 

 and they thrust themselves in between the elements of the tissue of the envelope as they 

 grow in the direction of the subhymenial layer, into which they send their many branches 

 and spread abroad between the points of insertion of the paraphyses. Finally the 

 asci appear as lateral branches of the last order on these subhymenial spreading 

 hyphae, which, as has been already said, grow between the paraphyses and in the same 

 direction with them towards the outer surface of the hymenium. The long-continued 

 successive formation and introduction of new asci at all points is the chief cause at 

 least of the surface-enlargement mentioned above, and of the exposure and often even 

 of the convexity outwards of the hymenium. Janczewski's observations have been 

 confirmed in the case of several species by Borzi, who has also described an allied 

 form, a species of Ryparobius, in which every shoot from the ascogenous cell becomes 

 an ascus directly. Borzi's view respecting the fertilisation of the archicarp is not 

 supported by any other case. 



6. The development of the sporocarp of Pyronema confluens (Peziza, P.) was 

 described by myself, but imperfectly, in 1863. Tulasne then added something to re- 

 statements. Kihhnan's recent examination of the species gives the following results 

 (Figs. 96-99). The Fungus spreads the stout filaments of its mycelium over wide 

 spaces of ground, especially where charcoal has been made or fires have burned. 

 The inception of the young sporocarp is preceded by the formation of groups of 

 obliquely erect curved branches, which in their turn put forth many branchlets. Some 

 of these, usually two in each group, swell strongly and form a few short bifurcations, 

 which grow in a direction vertical to the substratum and then cease their longi- 

 tudinal growth. The bifurcations form together an erect loose tuft or rosette (Figs. 

 96, 97 A), and some of them terminate in a short roundish cylindrical cell which 

 remains sterile. The extremities of others become either archicarps or antheridia 

 (Fig. 97 A,B). The former are broadly club-shaped bodies consisting of a much 

 inflated and usually somewhat curved cell, densely filled with protoplasm and borne 

 on one or two disk-shaped stalk-cells; the antheridia are the club-shaped terminal 

 cells of the branches of the bifurcations, about the same height, but only half as broad 

 as the archicarps. Several, at least two or three, organs of both kinds are present in 

 each rosette, and no other relations than those stated between the points of origin of 

 each pair of dissimilar organs have ever been observed. When the two kinds of organs 

 have reached the shape and length which have been described, each archicarp puts out 

 a broad protuberance near its apex, which grows rapidly into a blunt cylindrical tube 

 filled full with protoplasm ; and the tube becoming bent like a bow in a plane differently 

 disposed in different individuals, grows on towards a neighbouring antheridium, and 



