lO FIRST GROUP. —THALLOPHYTES. 



produced. These spores swell at various points in damp air and put forth germ-tubes ; 

 if these find their way to the young flowers of the Rye or some related grass, they de- 



FlG. 67. Clavicefs Pnrpiiiea. A a sclerotium (Ergot) forming stromata cl, nat. size. B upper part of a stroma in 

 longitudinal section ; cp the perithecia slightly magn. C a perithecium with the surrounding tissue highly magnified ; at 

 cp its orifice, hy hyphae of the head of the stroma, sh epidermal layer of the same. D an ascus ruptured and discharging 

 its spores. After Tulasne ; C and D highly magnified. 



velope in them into sphacelia, as Kiihn informs 

 us, and thus complete the cycle of development. 



4. DISCOMYCETES'. In order to give as 

 clear an illustration as possible of the mode of 

 formation of a perfect fructification in this sec- 

 tion, we may take as the next example As- 

 cobolus furfuraceus as described by Janc- 

 zewski. Fig. 68 gives a vertical section through 

 the entire fructification of this Fungus, which 

 is still connected with a portion of the myce- 

 lium ; the figure is diagrammatically drawn to 

 simplify it and at the same time make it com- 

 plete. The archicarp c and the antheridial 

 branch / are formed on branches of the myce- 

 lium in. The former consists of a row of broader 

 but shorter cells, and is much curved. The 

 antheridial branch with its slender branchlets 

 lays itself across the anterior portion of the 

 archicarp and closely embraces its cells. As the 

 result of fertilisation one of the middle cells of 

 the archicarp, which is also known as the ascogone, grows more vigorously than the rest. 



Fig. 68. Enlarged diagrammatic section of the fruc 

 WnzMon oi Ascobolus/ur/uraceits; >k mycelium, c archi- 

 carp, / antheridial branch, s ascogenous tubes, a the asci, 

 rp the tissue of the fructification from which the paraphyses 

 Designed from Janczewski's figures. 



^ De Bary, Ueber d. Frachtentwickl. d. Ascomycet. Leipzig, 1863. — De Bary u. Woronin, Beitr. z. 

 Morph. u. Phys. d. Pilze, Frankfurt 1866, 2^ Reihe (Abh. d. Senck. Ges.^ — Tulasne in Ann. d. sc. nat. 

 1866, V. ser. t. VI. p. 217.— Janczewski in Bot. Zeit. 1871, No. iS.— Brefeld, Eot. Unters. iiber 

 die Schimmelpilze, Heft. .\. 



