1 64 THE NORTH AMERICAN SLIME-MOULDS 



the peculiar gleaming of the metallic tints, displayed by all the 

 structures. These particulars we have not been able to verify. 

 Such characters may be incident to age or conditions of devel- 

 opment. At all events, in forms which in all other respects 

 seem to agree exactly with Rostafinski's descriptions, the colors 

 are dull and without any noticeable iridescence. The spores in 

 our specimens are also a little larger than quoted. Rostafinski 

 gives 5-6.5 jji\ Massee, 5-7 p. 



5. CRIBRARIA AURANTIACA Schrader. 



PLATE XVII., Fig. 3. 

 1797. Cribraria aiirantiaca Schrad., Nov. Gen. Ft., p. 5. 



Sporangia gregarious, spherical, dusky or yellowish stipitate, 

 nodding ; the calyculus variable, generally prominent, more or 

 less distinctly marked by fine, delicate radiating venules, the 

 margin denticulate, the teeth numerous and slender, supporting 

 the well-defined globose net ; network made up of very tenuous 

 threads, forming rather large three to five sided meshes with 

 small, irregular brownish nodules and showing only here and 

 there a free extremity ; stipe generally short, two or three times 

 the diameter of the sporangium, sometimes longer, tapering 

 upward, brown, slender, arcuate above ; spore-mass yellow or 

 ochraceous, spores by transmitted light colorless, 5-6 /^, almost 

 smooth. 



This widely distributed species is generally recognized by the 

 large sporangia, -5-.9 mm., comparatively short stipe, simple 

 net, and more or less orange color. The color is an uncertain 

 thing even in the sporangia, which rise from one plasmodium. 

 Schrader, however, made this feature so far diagnostic that 

 he placed the more pronouncedly yellow forms in the species 

 C. aurantiaca and set off as C. vnlgaris forms in which more 

 dusky tints prevail. The dark-colored forms have also usually 

 longer stipes, but so much is dependent upon the climatic condi- 

 tions prevalent at the time of fruiting, that this feature also is 

 indeterminate. Rostafinski's figures, 21 and 26, Tab. II., show 

 the characteristic nodules and the typical net structure. It is 



