240 PETCH : THE FUNGI 



somewhat flattened, about 1 cm. thick. Some were united 

 to the comb by a tangled mass of fine hyphae, while others 

 were apparently growing from the sides of the cavity. The 

 question whether these were connected with Xylaria nigripes 

 or the Xylaria whose conidial form appears in bell jar culti- 

 vations was settled by placing them under bell jars on damp 

 filter paper where in the course of a fortnight they produced 

 the ascus form of Xylaria nigripes. 



As far as the conidial forms are concerned, the natural 

 course of events agrees precisely with the results of that pot 

 cultivation which was formerly regarded as abnormal. Part 

 of the comb on which the branched stromata of PL XIII. were 

 grown was planted 3 inches below the surface in a pot on 30th 

 October, 1905. On 10th November three stromata appeared. 

 They were longer, narrower, and more regularly cylindric than 

 all previous forms, and did not show the apparent cap. 

 Instead, they tapered off to a long point, which in course 

 of growth became twisted, but finally they straightened out, 

 becoming about 3 centimetres long and 1 "6 millimetres broad, 

 with a thinner black stem sharply defined from the 

 conidiferous layer, and a central black core. The conidia 

 were narrow oval, 4-6 x 2 a*, borne at the apex of simple 

 horizontal basidia, and they did not germinate in water or 

 comb extract. On 17th November three more were produced : 

 these were rather thicker and one was bitid. but the structure 

 and conidia were the same. On 27th November, however, a 

 HiriL'le simple stroma developed of the same type as those in 

 other pot cultivations, and this was succeeded by another of 

 the same kind on 4th December. The first of these were the 

 conidial stages of Xylaria nigripes, while the later ones 

 were the conidial form already described. 



We now return to the later stages of the conidial forms 



which succeeded Xylnrui mgri/xs from combs in situ at the 



lining of AugUBt, 1006. Several specimens whose coni- 



diophore had been determined to be identical with those in 



bell j.ir cultivation-; were marked and t heir development noted. 



