DEVELOPMENT OF THE GEOGLOSSACEAE ■ 



G. H. Duff 



Although a number of investigators have contributed develop- 

 mental studies on the Ascomycetes and very substantial progress 

 has been made, our knowledge of the ontogeny of the higher forms 

 of these fungi is still far from complete. In consequence, our 

 present systems of classification are full of gaps, and our concep- 

 tions of the affinities of these plants are often contradictory or 

 mere guesses. For the elaboration of a satisfactory system of 

 classification and for the consolidation of our ideas regarding 

 relationships, it is requisite that the ontogeny of a much larger 

 number of representative species be worked out. 



This investigation has been confined to the Geoglossaceae. 

 Observations have been made on practically complete stages of 

 Cudonia lutea, Spathularia velutipes, and Trichoglossam kirsutum, 

 and on some of the critical features of Leotia. Heretofore studies 

 in this family have been restricted to three species of the genera 

 Leotia and Mitrula. 2 The chief interest centers around Cudonia 

 lutea and Spathularia velutipes because of the remarkable ascogonia 

 possessed by these plants, and because of the conspicuous veils 

 which render obvious to the naked eye their angiocarpous nature, 

 and which have long stood in opposition to the distinction by which 

 Schroeter 3 separates the Helvellineae from the Pezizineae. 



The youngest stage of Cudonia lutea which has come under 



minute cushion of interw 



threads measuring but 84 ju in height. At the center of this 

 loose assemblage of threads may be seen a small but definite group 

 of hyphae which are rendered conspicuous by their size and stain- 

 ing qualities. These are not ascogonia, as might at first be 



'Preliminary communication. 



2 Dittrich, G., Zur Entwickelungsgeschichte der Helvellineen. Cohn's Beitrage 

 8:1. 1918. 



Browx, W. H., The developement of the ascocarp of Leotia. Bot. Gaz. 



5o:443-459- 1910. 



3 Schroeter, J., In Ekgler and Prantl, Die natiirlichen Pflanzenfamilien. 



34i] [Botanical Gazette, vol. 69 



