JOHNSTON. — ON CAULOGLOSSUM TRANSVERSARIUM. 71 



Fla. (Ravenel, 1878) ; Eustis, Fla. (Thaxter, October, 1897) ; Tuskegee, 

 Ala. (Beaumont, aestate, 1853). 



Affinities. 



In comparing Rhopalogaster with other genera, certain general resem- 

 blances are evident in several directions. Its gross characters have led, 

 as has been already mentioned, to its close association with Podaxon in 

 the group of Podaxaceae, which in turn have been placed by different 

 authorities in different Gastromycetous orders. Fries, for example, as 

 well as a majority of the earlier writers, regarded Cauloglossum trans- 

 versarium as closely related to the species of Podaxon and Secotium, 

 while Fischer (7), in his recent revision of the Gastromycetes (1898) 

 has removed Podaxon to a new group, the Plectobasidiineae, leaving 

 Cauloglossum with Secotium in the Hymenogastrineae. 



That Rhopalogaster should be separated from the Podaxaceae, where, 

 however, the other species of Cauloglossum, namely, C. elatum, C. aegypti- 

 acum, and C. novo-zelandicum, should probably be referred, is clearly 

 evident when one examines the structure characteristic of this group. 

 The stipe of Podaxon is hollow and usually bulbous at the base ; the 

 peridium is scaly, and opens either by the falling off of the scales or 

 simply by longitudinal cracking; capillitium threads are present, either 

 rudimentary or well developed ; the spores differ in form; and the gieba 

 becomes a powdery mass at maturity. As all of these characters are 

 distinctly absent in Rhopalogaster, and as Podaxon is the only one of the 

 Plectobasidiineae which is at all similar to the type under consideration, 

 Rhopalogaster manifestly cannot be included with the Podaxaceae. The 

 only alternative group which remains to be considered is that of the 

 Hymenogastrineae under which Secotium is now placed by Fischer. 



According to Fischer's revision, the Hymenogastrineae include three 

 sub-groups, the Secotiaceae including Cauloglossum, the Hysterangiaceae, 

 and the Ilymenogastraceae. The Secotiaceae according to Fischer's 

 definition are characterized as follows : " Die Gleba ist von einer axilen, 

 sterilen Columella durchsetzt, welche sich nach unten in einer Stiel 

 fortsetzt. Die Tramaplatten gehen von der Peridie ab und siud deut- 

 lich gegen den unteren Teil der Columella gerichtet," and also " Bei 

 der Reife lost sich meist die Peridie an ihrem unteren Rande von Stiele 

 ab und kann sich mehr oder weniger deutlich ausbreiten nach Art des 

 Hutes der Agaricaceen." As has been shown on a preceding page, the 

 tramal plates in Rhopalogaster, on the contrary, extend from the colu- 

 mella toward the peridium, and the persistent peridium does not break 



