White: Tylostomaceae of North America 423 



possible. Mr. E. Bartholomew has kindly loaned material, for 

 the better description of one species, and Mr. E. S. Salmon has 

 kindly looked up some data at Kew, England. 



Special thanks are due to Professor Charles H. Peck, of Al- 

 bany, for material and suggestions, and more especially to Pro- 

 fessor L. M. Underwood, of Columbia University, under whose 

 direction the work has been undertaken and whose private collec- 

 tion has furnished considerable additional material. 



The genera of the family Tylostomaceae may be recognized 

 by the following synopsis : 



Peridium opening by an apical mouth. 



Peridium with a collar underneath, formed about the cylindrical stem ; volva in- 



definite. 



I. Tylostoma 



Peridium without a collar ; stem much enlarged where it joins the peridium ; 

 volva cup-like, flaring. II. Chlamydopus 



Peridium circumscissile. 



Peridium hemispheric or nearly plane below, dehiscing at the margin of the 



plane of the hemisphere. III. Battarrea 



Peridium spherical, dehiscing at the equator. Sphaericeps (extra-limital). 



Peridium opening irregularly. 



Peridium readily separating from the stem ; capillitium free. 



IV. Queletia 

 Peridium closely attached to the stalk ; capillitium embedded in a membranous 



tissue. V. Dictyocephalos 



L TYLOSTOMA Pers. R6mer, Neues Mag. Bot. I : 86. 1794 



The first reference to a plant certainly belonging to Tylostoma, 

 is to be found as early as 1696, in Ray's Synopsis * under the 



■ 



name of Fungus pulverulentus minimus. He describes it in a few 

 Latin words, " Pediculo longo, insidens. In agris circa Londinum," 

 and adds in English, •« the least dusty mushroom, with a long foot- 

 stalk, collected by D. Tancred Robinson, M.D." The next men- 

 tion is made in 1700 by Tournefort f who also gives the first figure 

 of a Tylostoma ; this has the characteristic short tubular mouth of 

 T. pedunculatum, a slender, smooth stem, and closely resembles 

 specimens of this plant found in our own country. Micheli % next 

 figured the other variety of T. pedunculatum under the name, squa- 

 mosum. This figure is not so easy to identify as that of Tournefort ; 



Syn. Meth. Stirp. Brit. 2d ed., 16. 1696. 

 tlnst. rei Herb. 1 : 563. pi. jjz.f. E, F. 1700. 

 \ Nova Plantarum Genera, 218, nos. 10 and It. //. <?7- /■ '• *7 2 9- 



