To anyone who will read the account of the species as given by the English Mon., 2nd ed., p. 183, it is immediately apparent that the author has in mind a different form from that seen and described in our territory and previously noted by the authors of Europe. These from Schrader down, agree in portraying a brunescent form with yellow spores; Mr. Lister enters it with the cyanic series and so describes and figures it throughout. Schrader figures a nut-brown species; Rostafinski uses that descriptive term in connection with the general appearance when fresh, but gives the spore-mass yellow; only in the stipe does he find another tint, nut-brown-purple. The figure, 145 in the Monograph now before us portrays, except in color, our C. tenella exactly. Dr. Rex, Bot. Gaz., XIX., 398, compares the present species with C. minutissima, and C. tenella with C. dictydioides; which is correct for the American presentation of the species named. C. dictydioides is certainly our presentation of C. intricata, a geographic species at the least; but if C. microcarpa is purple we have of it no representation; our forms under that name are closely related to C. tenella, a yellow-spored species, and might perhaps be there referred; have, however, somewhat larger spores.
12. Cribraria violacea Rex.
[Plate XVII]., Fig. 8.
- 1891. Cribraria violacea Rex, Proc. Phil. Acad., p. 393.
Sporangia scattered or gregarious, very small, .2 mm. in diameter, violet tinted, erect, stipitate short, about one-half the total height, concolorous, slender, tapering upward; calyculus crateriform, persistent, or marked with minute plasmodic granules; the net rudimentary or poorly developed, the meshes large, irregular, the nodules also large triangular, violaceous; spores pale violet in mass, by transmitted light reddish, 7–8 µ, minutely warted.
A very minute but well-marked species discovered by Dr. Rex in Wissahickon Park, near Philadelphia, otherwise very rare. Lister, however, reports it from England. In minuteness to be compared with C. minutissima, from which its color instantly distinguishes it. Dr. Rex reports the plasmodium as "violet black." All our specimens are on very rotten wood, basswood, Tilia americana.
13. Cribraria purpurea Schrad.
- 1797. Cribraria purpurea Schrad., Nov. Gen. Pl., p. 8.
Sporangia gregarious, large, 1 mm. in diameter, dark purple, erect, stipitate, depressed-globose; stipe concolorous, furrowed, about twice the diameter of the sporangium in length, with a distinct hypothallus; calyculus persistent, less than half the sporangium, obscurely ribbed, marked by concentric plications, the margin toothed; the net poorly differentiated, the meshes irregular in form and size, as are also the flat, unthickened nodes, the threads pale, free ends short and not numerous; spore-mass purple; spores by transmitted light, pale or colorless, 5–6 µ, smooth.