I40 BASIDIOMYCETES 



referred to the little known European B. phalloides, and still an- 

 other species has recently been described from Nevada.* 



The earth-stars form an exceedingly interesting group of organ- 

 isms and are represented with us by three well-marked genera. 

 Of these Astraeus is the most common, being found everywhere 

 in sandy soil ; its outer peridium which in the early stages covers 

 the inner and forms a compact ball, splits into several rigid star- 

 like teeth which spread out when moist and contract when dry so 

 as to again fold over the inner peridium ; this peculiar sensitive 

 ness to moisture has given the plant the specific name, hygro- 

 metricus. When dry it is rolled about by the wind, as it severed 

 its mycelial connections that produced it as soon as its spores 

 were mature, and as it is tumbled along it scatters its spores over 

 a wide extent of territory ; when rain or the dewy night overtakes 

 it, it absorbs the moisture and spreads itself out, to take up its end- 

 less march as sun and wind again appear to reduce it once more 

 to a ball and set it rolling. 



The true earth stars belong to Geastcr which is represented in 

 this country by nearly twenty species ; some of these form stars 

 three inches across while the smallest are often less than an inch ; 

 some, like G. triplex, show three layers to the peridium ; G. 

 fornicatus and some others become arched up on their star tips so 

 as to be able to sift out their spores more readily. Myriostoma, 

 as noted above, contains a single rare species which has probably 

 been overlooked, and will likely be found to have a wide distribu- 

 tion. Tylostonia has a slender stalk usually less than one-fourth 

 of an inch in diameter ; a half dozen species occur with us, of 

 which T, Dianunosuui is most widely distributed. Queletia, an- 

 other stalked genus, has thicker stems, and opens irregularly in- 

 stead of apically as in the last named genus ; its single species is 

 very rare, having been reported thus far from a single station only.f 



Secotium and Podaxon are usually rare, though the former is 

 sometimes found abundantly in cultivated fields and pastures ; 

 with Gyrophragmium it forms an apparent passage to the agarics 

 and for this reason a careful morphological study of these forms 

 is a desideratum. Cauloglossum contains one imperfectly known 

 southern species. 



* Batarrea attennata Peck, Bull. Torrey Bot. Club, 22: 208. 1895. 

 f Trexlertown, Pennsylvania. 



