80 THE NORTH AMERICAN SLIME-MOULDS 



The genus contains, so far, but a single species : 



i. CIENKOWSKIA RETICULATA (Alb. and Sc/tzu.} Rost. 

 PLATE XIV., Figs. 2, 2 a, zb. 



1805. Physarum reticulatum Alb. and Schw., Cons. Fung., p. 90. 



1829. Di tier ma reticulatum Fries, Syst. Myc., III., p. 112. 



1873. Cienkowskia reticulata (Alb. and Schw.) Rost., Versuch, p. 9. 



Plasmodiocarp an elongated, irregularly limited, close-meshed 

 net, closely applied to the substratum, the wall thin, transversely 

 regulose, and roughened, dull orange yellow splashed here and 

 there with scarlet, within marked by transverse calcareous 

 ridges, supporting in part the calcareous system of the capil- 

 litium ; capillitium of delicate, rigid, reticulating yellow tubules 

 or threads with numerous free, uncinate or sickle-shaped branch- 

 lets, and large, irregular, calcareous plates, more or less trans- 

 verse to the axis of the sporangium attached to the peridial 

 walls, as if to form septa, ordinary calcareous nodules few ; 

 spore-mass jet-black, spores, by transmitted light, violaceous, 

 minutely roughened, 9-10 p. 



A very rare species, as it appears, easily recognized by the 

 Coddington even, much more by the microscopic characters 

 quoted ; probably often overlooked by the collector, as to the 

 naked eye it presents the appearance of some imperfectly 

 developed, dried-up plasmodium. Very unlike Physarum scrpnla 

 Morgan, not infrequently offered by collectors as Cienkowskia. 

 It is Diderma reticulatum of Fries, who, strangely enough, 

 thought it might be a plasmodial phase of Diderma (i.e. Leo- 

 carpus} vernicos2im (Syst. Myc., III., p. 102). 



8. Leocarpus (Link) Rost. 

 1809. Leocarpus Link, Diss., I., p. 25. 



Sporangia sessile, or short stipitate ; peridial wall double, the 

 outer thick, destitute of lime, polished, shining within and with- 

 out, the inner very delicate, enclosing the capillitium and spores ; 

 capillitium of two, more or less, distinct systems, the one a deli- 

 cate network of hyaline, limeless threads, the other calcareous 



