202 THE NORTH AMERICAN S LIME-MOULDS 



acuminate, spiral ridges three or four, with traces of longitudinal 

 striae ; spore-mass golden yellow, spores beneath the lens pale 

 yellow, globose, delicately reticulate, about 10 p. 



Very common. Easily recognized by its bright yellow color 

 and conspicuous reticulate habit. The plasmodium is yellow, 

 at least upon emergence, and passes almost without change to 

 fruit. Found on rotten logs of every description, on the lo wer 

 surface. In the Mississippi Valley the lower surface of planks 

 used in the construction of sidewalks appears to be a favorite 

 habitat. 



Common west to the Rocky Mountains, south to Mexico and 

 Nicaragua. 



2. HEMI'TRICHIA KARSTENII (Rost.} Lister. 



1876. Hemiarcyria karstenii Rost, Mon. App., p. 41. 

 1891. Hemiarcyria obscura Rex, Proc. Phil. Acad., p. 395. 

 1894. Hemitrichia karstenii Lister, Mycetozoa, p. 178. 



Fructification plasmodiocarpous, with a tendency to form 

 distinct sessile, globose sporangia, brownish red in color ; capil- 

 litium a sparingly branched loose network, with free ends few, 

 the thread marked by seven or eight faint spirals, the interspaces 

 narrow, dull red in color, and 2.5 //.in diameter; spores yellow, 

 delicately warted, 10-10.5 /a. 



We have not seen this species, and in the description have 

 followed Dr. Rex, I.e., as being more to the point for American 

 forms. It is not improbable that the American material may 

 after all be distinct, as discrepancies, if one may judge by 

 descriptions, are not few. Lister, who had a slide from Dr. 

 Rex, considers the European and American forms the same. 



Montana Anderson. To be looked for north and west. 



3. HEMITRICHIA OVATA (Pers.~) Macbr. 



1796. Trichia ovata Pers., Obs. Myc., I., p. 61, and II., p. 35. 



1863. Trichia abietina Wigand, Pringsh. Ja/ir., III., p. 33, Tab. ii., Fig. n. 



1875. Hemiarcyria ivigandii Rost., Mon., p. 267. 



Sporangia crowded or sometimes closely gregarious, sub- 

 globose or turbinate, shining yellow, sessile, the peridium thin, 



