184 ENDOSPOEE^. [AKCYEIA. 



KEY TO THE SPECIES OF ARG7RIA. 



A. Spores 9 to 11 /a diam., sporangia orange-red or buff: — 



Sporangia ovoid, wall reticulated. 1. A. ferruginea 



Sporangia clavate, wall papillose. 2. A. versicolor 



B. Spores 6 to 8 /* diam. : — 



A. OapilUtium attached to the cup — 



Capillitium closely spinulose, grey, or yellowish-grey. 



3. A. alhida 



Capillitium marked with cogs and half -rings ; sporangia 

 red, ovoid, or subcyhndrical. 4. A. ptmicea 



Capillitium marked with transverse bands and minute 

 spines ; sporangia flesh-coloured, turbinate, small. 



5. A. insignia 



B. OapUlitium free from the cup — 



a. Network of capillitium expanding, not droopiug — 



Capillitium marked with cogs and spines. 



6. A. incwrnata 



Capillitium marked with cogs, spines, and three to 

 foiir indistinct spiral bands in addition. 



1.,A. ■ 



h. Network of capillitium much elongated, drooping^- 



Sporangia buff ; wall evanescent above. 



8. A. flava 



Sporangia red ; wall persistent above in shield-Hke 

 fragments. 9. A. (Erstedtii 



1. A. ferruginea Sauter, in Mora, xxiv., p. 316 (1841). Plas- 

 modium rose-red, in rotten wood. Total height 1 to 2 mm. 

 Sporangia ovoid, stipitate, crowded, 0'7 to 1'3 mm. high, 0'5 to 

 1 mm. broad, orange-red, or more rarely pale ochraoeous; cup of 

 sporangium even, shining, funnel-shaped, or at length nearly 

 flat, marked with round-meshed reticulations on the inner side. 

 Stalk cylindrical, 0-3 to 0'8 mm. long, 0-05 to 0-15 mm. thick, 

 red, rarely white, arising from a well-developed membranous 

 hypothaUus; filled with spore-hke cells. Capillitium an elastic 

 network of .freely branching yellow-b:c.own threads, 5 to 8 ;«, diam., 

 diminishing to 2 to 3 /* diam. towards the base, triangular or 

 oval in section, thickened on one side with transverse bars or 

 reticulations, on the other two sides marked with a broken re- 

 ticulation or with warts, often spinulose throughout ; a few 

 sparingly branched slender threads penetrate the tube of the 

 stalk without attachments to the cup ; free ends with rounded or 

 pointed tips are not unfrequent, but often wanting. Spores pale 

 red or ochraceous, faintly and closely warted, 8 to 11 /«, diam. — 

 Eost., Mon., p. 279 ; Cooke, Myx. Brit., p. 73, fig. 194 ; Blytt, Bidr. 



