ARCYRfA 195 



size, those above 67 ft, below 3 ft, abundantly branching, marked 

 by conspicuous reticulations formed by the intersection of nu- 

 merous vertical plates or ridges ; spore-mass reddish, spores by 

 transmitted light pale ochraceous, distinctly warted, 10-12 ft. 



This species is distinguishable at sight by the peculiar color 

 and form of the sporangia. Mr. Durand in Bot. Gaz., XIX., 

 pp. 89, 90, gives a careful study of the form. The same author 

 declares the dehiscence circumscissile. We cannot distinguish 

 A. aurantiaca Raunk. from the present form. 



Rare. Maine, New York. 



8. ARCYRIA DENUDATA (Linn.') Sheldon. 



PLATE II., Figs. 5, 5 a. 



1753. Clathrus denudatus Linn., Syst. Nat., p. 1179. 



1794. Arcyria punicea Pers., Rom. N. Mag. Bot., I., p. 90. 



1895. Arcyria denudata (Linn.) Sheld., Minn. Bot. Studies, No. 9, p. 470. 



Sporangia crowded or gregarious, ovoid or short cylindrical, 

 tapering upward, red-brown, stipitate ; peridium evanescent 

 except the plicate calyculus ; stipe about equal to the expanded 

 capillitium, concolorous, plicate or striate, ascending from a 

 small hypothallus ; capillitium attached to the whole inner sur- 

 face of the calyculus, and connat'e with it ; hence not deciduous, 

 bright red or carmine when fresh, turning brown or paler with 

 age, the threads even, about 3 ft, adorned with a series of rather 

 distant cogs or half rings, which form around the thread a 

 lengthened spiral ; spore-mass red or reddish brown, spores by 

 transmitted light colorless, nearly smooth, 6-8 ft. 



This species is easily distinguished from all others of similar 

 tints by the attachment of the capillitium. In this respect it 

 corresponds with the following species. In the adornment of 

 the threads it is like A. incarnata. It is by far the commonest 

 species of the genus, and probably enjoys a world- wide distri- 

 bution. To be found at all seasons on the lower side of fallen 

 sticks, Populus, Tilia, etc. 



Micheli, PL XCIV., shows that he had the present species. 

 The description given by Linne is worthless, but helped out by 



