SECT. I 



CRYPTOGAMS 



395 



mycelium by their intimate union, especially at the periphery, into a comjiact 

 mass of pseudo-parenchyma (Fig. 110). These elongated dark- violet scleuotia, 

 which jiroject in the form of slightly curved bodies from the ears of corn, are 

 known as Ergot, secale cornutum (Fig. 323, B). The sclerotia, copiously supplied 

 witli reserve material (fat), eventually fall to the ground, where they pass the 

 winter, and germinate in the following spring when the Rye is again in flower. 

 They give rise to bundles of hyphae which produce long, stalked, rose-coloured 

 globular heads (C). Over the surface of the latter are distributed numerous sunken 

 jierithecia (Z), E). Each perithecium contains a number of asci with eight long, 

 filiform ascospores, which are ejected and carried by the wind to the inflorescences 

 of the grass. 



Nedria ditissima C^) is a very injurious parasitic fungus which inhabits the 

 cortex of various trees and causes the canker of fruit trees. It is propagated 

 in summer by means of slightly curved, fusiform, multicellular conidia, and 

 in winter and spring forms small red perithecia which are closely crowded 

 together. 



Official. — Ergot is the sclerotium of Claviceps purpurea. 



Order 4. Discomycetes C^) 



The Discomycetes are distinguished from the other orders by their open 

 apothecia, which bear the hymenium, consisting of asci and paraphyses, freely 

 exposed on their upper surface (Fig. 325). The different groups exhibit great 

 diversity as regards the manner of development of their fructifications. 



Fk;. 3"24. — I'czizu anrantiwo. 

 (After Krombholz, uat. size.) 



^^ 



Fin. 3'25. — Ldchnea imlclicrrima. Apotheciuiii ruptiuvd, 

 sliowiiiL; old and young asci between the paraphyses. 

 (After WoRONiN, from v. Tavel.) 



The great majority of the Discomycetes, of which the genus Peziza may serve 

 as a type, grow on living or dead vegetable substances, especially upon decaying 

 wood, but sometimes also on humus soil. They j'l'oduce saucer- or cup-shaped 

 fructifications of a fleshy or leathery consistency, and usually of small dimensions. 

 One of the largest forms, Peziza aurantiaca (Fig. 324), has irregularly bowl-shaped 

 fructifications, which may be seven centimetres broad and of a bright orange-red 

 colour, while in most of the other species they are grey or brown. Such cup- 

 shaped fructifications are termed apothecia. 



