48 



INTRODUCTION TO THE STUDY OF FUNGI 



Fig. 28. — PseTuloperidia of 



Accidium. 



which contain globose spores developed in chains (Fig. 28); 

 and possibly the Hystcriaccae, in which the receptacles are 

 often closed and elongated, but in some instances are gaping 

 in moist weather, so as to expose a compact disc of parallel asci, 

 combined witli paraphyses, after the manner of Pcziza. This 

 family falls intermediate between 

 those with a cup-shaped receptacle 

 and the following group, in which 

 the receptacle is a closed perithecium, 

 but inclined more towards the 

 former than the latter. It will be 

 observed, in examining more closely 

 into the morphology of these groups, 

 that the preponderance of species which possess a cup-shaped 

 receptacle are sessile on the mycelium, without the inter- 

 vention of a carpophore, in the sense to which we have here 

 limited that term. 



We pass now to the representatives of that large mass of 

 Fungi in which the receptacle is wholly closed, with the ex- 

 ception of a terminal pore, as included under the general term 

 perithecium (Fig. 29). In all essential features the fructifica- 

 tion is the same under the two forms in which it presents 

 itself, the ascigerous and the stylosporous. The former is that 

 of the Pyrenomycetes and consists of cylindrical sacs, or asci, 

 with linear paraphyses intermixed and packed closely side 

 by side. In this respect the fructification resembles that of 

 the Discomycetes, only that the disc, or upper surface, is not 

 exposed, and hence not compacted. 

 The asci contain four or eight or 

 sometimes an indefinite number of 

 sporidia, which are either hyaline 

 or coloured, and simple or variedly 

 septate. The summit of the ascus 

 is normally imperforate. Exceptional instances could be 

 cited in which the ascus encloses but one or two sporidia, or 

 where no paraphyses can be detected. Up to the present no 

 clue has been found to the fertilisation of the sporidia, 

 whether by the fertilisation of the entire receptacle in its 

 earliest stage or that of the sporidia. In the case of some of 



Fk;. 29. — Peritliueium and 

 section. 



