206 THE NORTH AMERICAN SLIME-MOULDS 



liard's plates leave no doubt as to the forms he included. Gmelin 

 writes: "Thecse (membranae expansae superimpositae) inter se con- 

 natae seminibus nudiusculis replete." 



Why, in face of so good a description, Persoon changed the name 

 to that since current, Tubulina, is not clear. 



Fries thinks Mueller had an immature Arcyria before him, Syst. 

 Myc, III., p. 196. Tubulifera arachnoidea Jacq., 1778, is also an 

 uncertain quantity, insufficiently described. 



Key to the Species of Tubifera 



A. Hypothallus well developed, but not conspicuous. 



a. Pseudo-columellae none .... 1. T. ferruginosa 



b. Pseudo-columellae present at least in many of the tubules, 



2. T. casparyi 



B. Hypothallus prominent, columnar .... 3. T. stipitata 



1. TuBiFERA FERRUGINOSA (Batsch) Macbr. 



Plate I., Fig. 4; Plate VII., Fig. 8; Plate XII., Fig. 14. 



1786. Stemonitis ferruginosa Batsch, Elench., p. 261, Fig. 175. 



1791. Sphaerocarpus cylindricus Bull., Champ., p. 140, t. 470, III. 



1791. Tubifera ferruginosa Gmelin, Syst. Nat., 1472 {ex parte). 



1805. Tubulina cylindrica (Bull.) DC, Fl. Fr., 671. 



1875. Tubulina cylindrica (Bull.) Rost., Mon., p. 220. 



1894. Tubulina fragiformis (Pers.) Lister, Mycetozoa, p. 153. 



Sporangia crowded, cylindric or prismatic, elongate, connate, more 

 or less distinct above, pale umber-brown, generally simple though 

 occasionally branched above, the peridia thin, sometimes fragile, but 

 generally persistent, transparent, iridescent; hypothallus strongly de- 

 veloped, spongiose, white, often projecting beyond the aethalioid mass 

 of sporangia ; spore-mass umber-brown or ferruginous ; spores by trans- 

 mitted light almost colorless, plainly reticulate over three-fourths of 

 the surface, 6-7 fi. 



Not rare on old logs, mosses, etc., from Maine to Alaska. Ap- 

 parently more common north than south. Easily known by its long, 

 tubular sporangia packed with rusty spores and destitute of any trace 

 of columella or capillitium, the hypothallus explanate, rather thick, 

 but not columnar. A single plasmodium may give rise to one or sev- 

 eral colonies, at first watery or white, then red, of somewhat varying 



