42 H. MARSHALL WARD. 



The paraphyses now spring from the dense mass forming the inner 

 wall of the perithecium. The asci arise from among these, and have 

 therefore nothing to do with the " Woronin's hyphse," which have 

 disappeared in a slimy mass. Further details offer nothing new. 



In Claviceps, the young perithecium arises as a mass of small cells, 

 which rapidly divide and form a parenchyma-like mass. A hollow 

 then appears in the interior (reminding one in many respects of the 

 cleavage cavity in some animal embryos) by the separation of the cells. 

 The mass now consists of a thick basal portion, above which is a hollow 

 space roofed over in a dome-like manner by the upper cells. There is 

 no trace of an ascogonium or of " Woronin's hyphee " at any time ; 

 the asci arise by budding from the cells forming the floor of the cavity. 



Gordiceps and other species of both genera agree in the main with 

 what has been described. 



In summing up the foregoing, the author points out that while in 

 Polystigma we have morphologically the same organs as occur in the 

 Collemaceee (viz. spermatia, trichogyne and ascogonium), no sexual 

 process could be demonstrated. In Xylaria the sexual organ — at any 

 rate the ascogonium — is represented morphologically, but has become 

 functionless — it deliquesces and is absorbed before the asci arise; 

 these spring in a purely vegetative manner from the lining walls of 

 the perithecium. It is possible that certain facts observed in Ctccur- 

 bitaria point to the same end. 



In Clavicejw the perithecium is purely apogamous — no trace of an 

 ascogonium occurs, and the asci are produced by a vegetative process 

 of budding from the floor of the perithecium cavity. 



Putting together the foregoing facts, and what is known otherwise 

 of the allies of these Fungi, Fisch shows that the compound Pyreno- 

 mycetes present a series of forms which commence with a complete 

 differentiation of sexual organs (ascogyne, trichogyne, and spermatia), 

 and end in forms which are quite apogamous, and. with no trace of 

 sexuality. We may go further than this. 



Beginning with Podos}oliaira, in which a sexual process is possibly 

 still recognisable, we trace a series through the simple Pyrenomycetes 

 and the Discomycetes branching off from these, ending with the com- 

 pletely apogamous Chcetomiimi 1 and Pleospora. 2 In this series there 

 is no place for the composite Ascomycetes and Lichens — for although 



1 Van Tieghem, 'Compt rend.,' 1875; and 'Bull. Soc. Bot. Fr.,' 1876. 

 s Zopf, 'Bot. Zeit,,' 1879i p. 73. Bauke, 'Bot. Zeit.,' 1879, 



