— :>10 — 



being thinner and less compact has the same structure as that of Myxo- 

 theca; in both fungi every single ascus is situated in a loculus, but in 

 Cookella the asci are lying very closely together, sometimes pressing each 

 other and by tliis reason becoming somewhat irregular (cfr. as to our 

 fungus fig. 2o); further, there is no trace of the long pedicels so charac- 

 teristic in Myxotheca, as even the young asci are quite sessile. Finally 

 there is a distinct resemblance between the asci of Cookella and those 

 of higher ascomyceleous fungi (especially Perisporiaceae), the membrane 

 being well limited and in younger asci thickened in the apex, while the 

 ascus-membrane of Myxotheca at a very early stage becomes deliquescent 

 and indistinct. 



Thus Myxotheca is seen to present characters partly resembling to 

 and partly differing from those of Cookella, the phylogenetic position of 

 the first upon the whole appearing more primitive. In many respects 

 the accordance between our fungus and lower forms of the Plectascineae 

 is not to be mistaken; in this respect is namely to be pointed out: The 

 loculi are quite without ostiola, and the spores become liberated by lique- 

 faction of the asci and destruction of the stroma; the asci are developed 

 from different starting-points; further the above mentioned unevenness of 

 the peripheral hyphae suggests not unlikely a relation to the Gymnoascaceae 

 (cfr. GymnoascAis, Ctenomyces). The long pedicels of the asci, joining in 

 bundles from common starling-points — and the independence of the 

 spore-apparatus in the face of the surrounding stroma: both these charac- 

 ters seem to be primitive. On the other hand the spores themselves 

 have a highly differentiated form; it ought not to be overlooked, however, 

 that muriform sporidia appear even on the still low phylogenetic level of 

 the Myriangiaceae. 



The definitive placing of the fungus in the system can be undertaken 

 only when comparative examinations have been made on this too little 

 known domain — and more new forms eventually have been discovered; 

 until that Myxotheca most naturally finds its place among the Plectascineae 

 in nearest relation, as it seems, to the Gymnoascaceae. Upwards, if this 

 term be allowed, there are connecting points with the Myriangiaceae. 



Nostocotheca amhigua Starb., which benevolently was sent to us 

 from the Riksmuseum in Stockholm, presents no nearer connection with 

 our fungus; macroscopically it appears rather Erysiphe-Y\ke, and also the 

 microscopic characters seem to point towards the Perisporiales. namely 

 thereby, that the asci of each glomerulus are aggregated in a sort of 

 hymenium and separated from each other by paraphyses (cfr. Starback 1. c). 



Trinidad, Maravalli Valley, 30. 11. 91. 



Nectria subquaterna B. et Br. — fig. 3. 

 Synonyms (sec. Wee se in lit.). N. squamuligera Sacc. 1875, N. 



