SCHIZOTHYEIUM. 



Schizothyrium, Desmaz ; Ann. Sci. Nat., Ser. iii. vol. xi. 

 (1849), p. 360; Eehm, in Krypt.-Flor., Hyst., p. 75; Sacc, 

 Syll., ii. p. 723 (defined by mistake as having the spores 

 continuous). 



The present genus holds an intermediate position between 

 the Systeriaceae and the Phacidiaceae, leaning towards the 

 former in general habit, and towards the latter in the some- 

 what fleshy ascophore, which is not so carbonaceous and 

 rigid as in typical members of the Hysteriaceae. 



Schizothyrium ptarmicae. Desm., Ann. Sci. Nat., 

 Ser. iii. vol. xi. p. 361 ; Eehm, Krypt.-Fl., Hyster., p. 75, figs. 

 1-5, p. 63 ; Sacc, Syll., ii. n. 5569. 



Gregarious, innate, black, ^3 mm. across, circular or ellip- 

 tical, rather soft when moist, cells of escipulum small, very 

 compact, external ones blackish-olive, dehiscing by an elon- 

 gated or stellately radiating slit; asci cylindric-clavate, most 

 frequently containing only 2 spores ; spores elliptic-oblong, 

 or very slightly clavate, straight or very slightly curved, 

 smooth, ends obtuse, hyaline, 1-septate at maturity, 10-14 x 

 6-6 /u, ; paraphyses filiform, slender, septate, slightly thick- 

 ened, branched, and coloured above. 



Lahrella ptarmicae, Desm., Crypt. Fr., exs. n. 189. 



On living leaves ot Achillea piannica, forming very minute 

 black spots. 



Spermogonia. Perithecia almost plane, shield-like, circular 

 or very broadly elliptical, 300 /x diam., not provided with a 

 pore fur dehiscence, consisting of sinuuus, browninh cells 

 forming a pseudo-parenchyma ; sporidia ovate-oblong, 10 x 

 6-7 /J, ; contents cloudy, sometimes indistinctly divided 

 into two portions, hyaline, supported on short, cylindrical 

 basidia. 



Lahrella ptarmicae, Desm., exs. n. 149 (in part). 



Leptothyrium ptarmicae (Desm.) Sacc, Mich., ii. j). 114; 

 Sacc, Syll., iii. n. 3379. 



On stems of Achillea ptarmica. 



Schizothyrium aquilinum. Eehm, Krypt.-Flor., 

 Hyst., p. 75. 



Gregarious, covered at first by the adherent epidermis 

 rounded or elongated, deformed and rugulose, black, opaque 



