mucronata can not be used, as it certainly is not Schweinitz's plant 

 so illustrated (in Letter 64, Fig. 985), although nothing is known of 

 Schweinitz's plant excepting his figure. Cooke gives a good figure 

 under the name Xylaria mucronata, but he gets his idea from Berke- 

 ley's plant and his name from Schweinitz. Berkeley never connected 

 the two. 



Xylaria Zealandica is very similar as to clubs, and Cooke empha- 

 sizes the lines on the clubs, but describes the spores as 10 x 32-35, 

 which is very much larger than in the American plant. Probably it 

 is the same species. It is the only similar species where these lines 

 have been noted in the description. Theissen evidently considers it 

 a simple form of Xylaria arbuscula, as named by Saccardo from 

 some adventitious plants in a hothouse in Italy. In the original 

 sense this is a much larger plant with multiplex, fasciculate clubs, 

 and I think it is not proven that it takes simple forms like this. The 

 spores in the American plant are mostly 12-14 m i c - l n g- A few we 

 note 16-18 mic. and we saw one spore over 24 mic. It is evident that 

 the exact size of Xylaria spores is not important. Species based on 

 spore size alone are not of much value when one can find spores less 

 than 12 mic. and more than 24 mic. on the same slide. 



XYLARIA THEISSENII (Fig. 1007). Stem 

 long, 7-10 cm. slender, smooth, \-\Yi mm - thick, 

 rooting at base (from the ground). Club short 

 i-i]/2 cm -> tipped with a slender, filiform apex. 

 Perithecia partially imbedded, or almost free, form- 

 ing a tubercular club. Spores 9-10 x 24-28. 



This is a rare plant only known from Brazil. 

 We have seen only Theissen's exsiccata (No. 235), 

 kindly loaned us by Dr. Brenckle. Theissen labels 

 it, and includes it in his work as the second form 

 of Xylaria Thyrsus, but it has no analogy what- 

 ever to Xylaria Thyrsus, known only from Java 

 and India, and which has no carbonous crust, but 

 an entirely white, fleshy stroma, and is in fact not 

 a Xylaria. Nothing like "Xylaria" Thyrsus is 

 known from Brazil. In general appearance Xylaria 

 Theissenii approaches Xylaria filiformis, but is a 

 larger plant with much larger spores. We did not 

 break the specimens, and we do not know, but 

 we think probably that, like Xylaria filiformis, 

 it has no white stroma at all. 



If we were revising the genera of the large 

 Pyrenomycetes, we should propose a "new genus" 

 for "Xylaria" Thyrsus for it is entirely out of 

 place in the genus Xylaria. If this were done, 

 those who depend for determinations on the 

 "literature" would not make the mistake of re- 

 ferring to the species a true Xylaria. 



Fig. 1007. 



677 



