645 



cylindrical. Sporidia sublanceolate, continuous, brown, straight or 

 curved, 16-18 x3| //. This is a different thing from Sphceria ramu- 

 losa, Schw., which appears referable to Xylaria. 

 On branches, Indiana. 



D. Stroma broadly effused (Placoxylon). 

 * Externally colored, not black. 



H. perforatum, (Schw.) 



Sph&ria perforate,, Schw. Syn. Car. No. 45. 

 Hypoxylon perforatum, Sacc. Syll. 1431. 

 Exsicc. Rav. F. Car. V, 54. Rav. F. Am. 349, 350. Thum. M. U. 368. 



Stroma (on the bark or wood) superficial, effused or tubercular- 

 convex (2-4 mm.), often interruptedly confluent for several cm. in 

 extent, dark or purplish rust-color, dotted with the minute, white- 

 margined, punctiform ostiola. Coiiidial layer cinereous-white, pulver- 

 aceous. Conidia minute, ovoid or subglobose on short, subsimple or 

 branching hyphae. Perithecia submonostichous, globose, small (J-J 

 mm.), lying near the surface of the stroma, crowded, mostly not dis- 

 tinctly prominent. Asci cylindrical, 60-90x7-9 p. (p. sp.). with a 

 long, filiform base and overtopped by the filiform paraphyses, 8-spored. 

 Sporidia obliquely uniseriate, ovate, with the ends mostly obtuse, 

 nearly straight or subineq trilateral, dark brown, 10-14x5-7 //. Bears 

 a general resemblance to H. rubiginomm. 



On dead oak, maple, ash and other limbs, common; also on dead 

 petioles of Sabal serrulata, Florida (Calkins). 



H. rubiginosum, (Pers.) 



Sphceria rubigtnosa, Pers. Syn. p. n. 

 Hypoxylon rubiginosum, Fr. Summa Veg. Sc. p. 384. 

 Exsicc. Thum. M. U. 1071. Rav. F. Am. 654, 741. Plowr. Sph. Brit. 21. 



Stroma mostly broadly effused, but also occurring in small patches 

 2-4 mm. across, bright ferruginous-red, finally black, tolerably thick 

 (1-2 mm.), surface nearly even or distinctly mammillose from the pro- 

 jecting perithecia. Conidial layer pulverulent, thin, at first dirty 

 olivaceous-yellow, then bright ferruginous. Conidia obovate or oval, 

 very small, acrogenous on short, sparingly branched sterigmata. Asci 

 cylindrical, long pedicellate, 8-spored, with slender, filiform par- 

 aphyses, 60 x 6 fi (p. sp.). Sporidia inonostichous, ovate, inequilateral, 

 or nearly straight, dark brown, 10 x 15 p.. 



On decorticated limbs of various deciduous trees, common in this 

 country and in Europe; around Xewfield, N. J., mostly on Acer and 



