1918] 



BURT THELEPHORACEAE OF NORTH AMERICA. X 319 



a feature which it shares with H. Cacao. H. rigidula differs 

 from H. Cacao by having its intermediate layer bordered by 

 a prominent dark zone on its outer side, by being effuso- 

 reflexed, and with less black in the color of its hymenium. In 

 dried condition it is more rigid than H. tahacina and the 

 other species of its group with the exception of H. ruhiginosa, 

 from all forms of which it may be distinguished at sight by 

 less conspicuous setae when viewed with a hand lens and by 

 the much thinner, setigerous layer when sections are ex- 

 amined. So few spores of H. rigidula have been seen in the 

 preparations that the spore dimensions given are very doubt- 

 ful. My belief in the specific identity of H. fulvella is based 

 upon the similarity of sectional preparations; since noting 

 this similarity of structure, I have not had an opportunity 

 to confirm my opinion by placing the original specimens side 

 by side and comparing them with regard to general aspect. I 

 did not find H. pulcherrima when I was at Kew, and in reply 

 to my letter to Miss Wakefield concerning the original Fendler 

 number for this type. Sir David Prain has written, ' * With re- 

 gard to H. pulcherrima Mass., the specimen indicated by 

 Massee as No. 3721a was removed by him from a gathering 

 of H. fulvella B., the label of which, in Berkeley's handwrit- 

 ing, is 'Stereum fulvellum B. & C. 173, Venezuela.' Massee 

 named it on the sheet 'H. scruposa,' but evidently he changed 

 the name before publishing it." — It seems probable that in 

 the year following the publication of H. pulcherrima, Cooke 

 saw the specimen upon which it was based, still labelled with 

 only the herbarium name H. scruposa Massee and published 

 the latter. I have studied the specimen in Curtis Herbarium 

 \sihel\ed''Stereum fulvellum B. & C, Fendler, 173. Venezuela" 

 and found it to have the characteristic structure of H. rigidula 

 and H. fulvella and to agree well with the published descrip- 

 tions of H. fulvella, H. pulcherrima, and H. scruposa. 



Specimens examined: 

 Cuba: C. Wright, 529, type (in Kew Herb, and in Curtis 

 Herb.) ; Herradura, Earle & Murrill, 170, comm. by N. Y. 

 Bot. Gard. Herb. ; San Diego de los Banos, Earle S Mur- 

 rill, 219, comm. by N. Y. Bot. Gard. Herb. 



