ENTERIDIUM 211 



sericeo nitore insignis ; sed deinde sordescit e griseo in subfuscum ver- 

 gens." Sometimes the surface does indeed shine as silver! 



The fructification appears to be isolated in each case; the entire 

 Plasmodium consumed in a single plasmodiocarp. 



Widely distributed. Maine to California, and south. 



2. Enteridium Ehrenberg 

 1818. Enteridium Ehrenberg, Link and Spreng., Jahrb., Bd. II., p. 55. 



Fructification asthalioid ; the confluent sporangia inextricably inter- 

 woven, the walls perforate by large openings, the resultant network 

 of broad plates and bands widening at the points of intersection. 



The genus Enteridium is distinguished from Reticularis chiefly 

 by the more perfectly developed sporangial walls. These are every- 

 where membranous and do not show the abundant filiform dissipa- 

 tion so characteristic of Reticularia. The resultant structure in Re- 

 ticularia is a mass of more or less lengthened and anastomosing threads ; 

 in Enteridium, an exceedingly delicate but sufficiently persistent 

 sponge. The "net-like, three-winged skeleton" referred to by Ros- 

 tafinski results from the union at one point of three adjoining spor- 

 angia. Compare the section of the adjoining cells of a honeycomb. 



Of this genus there are but two or three species, all so far occur- 

 ring in our territory. 



Key to the Species of Enteridium 



A. Fructification umber brown \ E. splendens 



B. Fructification olivaceous 2. E. olivaceum 



C. Fructification minute, 1-2 mm 3. E. minutum 



1. Enteridium splendens Morg. 



Plate I., Figs. 1, \ a, \b; Plate XII., Figs. 4, 5. 



1876. Reticularia {!) rozeanum Rost., Mon. App., p. 33. 



1889. Enteridium rozeanum (Rost.) Wing., Proc. Phil. Acad., p. 156. 



1892. Enteridium rozeanum Wingate, Macbr., Bull. Lab. Nat. Hist. Iowa, 

 XL, p. 117. 



1893. Reticularia splendens Morg., Jour. Cin. Sac, p. 11. 

 1899. Enteridium splendens Morg., Morg. in litt. 



iEthalium pulvinate, even, or somewhat irregular, unevenly swollen 



