NORTH AMERICAN GEASTERS. 



7 



NORTH AMERICAN GEASTERS. 



BY A. P. MCBGAN. 



NoTK.— This article in a more popular form and with illustrations appeared in the 

 American -Vatitralist for October, 1884. The authorities on the subject are chiefly Fries' 

 Systenia Mycologicura and Dr. Cook's Grevillea, Vol. II. page 77 with the Illustrations. 



Geaster, Mich. Earth-star.— Receptacle double, consisting of 

 an outer and an inner peridium; outer peridium stellately divided into 

 several segments ; inner peridium dehiscing by a mouth at the apex ; 

 spores globose, echinulate. 



A. Pedicels several, 1 . 



B. Pedicel single : 



a. Mouth sulcate-plicate, 2, 3. 



b. Mouth ciliate-fimbriate, 4, 5. 



C. Pedicel wanting, spores small. 



c. Mouth sulcate-plicate, 6, 7. 



d. Mouth ciliate-fimbriate: 



a. Plants large, 8-10. 



b. Plants small, 11-13, 



e. Mouth dentate, 14. 



D. Pedicel wanting, spores large. 



f. Mouth ciliate-flmbricate, 15. 



g. Mouth lacerate, 16-18. 



A. Inner peridium with several pedicels and numerous mouths. 



1. G. coLiFORMis, Pers. Outer peridium multifid; inner peridium 

 depressed-globose, li— 2 inches in diameter, the mouths ciliate; spores 

 .0050 mm. Colorado, Prof. Chas. H. Peck. 



B. Inner peridium with a single pedicel^ mouth one. 

 a. Mouth sulcate-plicate. 



2. G. FORNiCATUS, Fr. Outer peridium double, subquadrifled ; 

 inner peridium subglobose,i—l inch in diameter; spores .0035— .0040mm. 

 Carolina, Curtis ; Schweinitz under G. quadrifidum. 



3. G. Brya?^tii, Berk. Outer peridium single, multifid ; inner 

 peridium sub-globose, f — 1 inch in diameter ; spores .0040— .0045 mm. 

 Xew York, Prof. Chas. H. Peck. 



h. Mouth ciliate-fimbriate. 



4. G. LiiviBATUS, Fr. Inner peridium subglobose, brownish, f— 1 

 inch in diameter ; spores .0040— .0045 mm. Alabama, Peters ; Carolina, 

 Curtis ; New England, Frost ; Ohio. 



5. G. MINIMUS, Schw. Inner peridium ovoid, white, about i of an 

 inch in diameter ; spores .0040— .0045 mm. East and South. 



C. Inner peridium sessile, tlie spores small, .003 — .005 mm. 

 c. Mouth sulcate-plicate. 



