TAXONOMY OF THE PILOBOLIDAE 207 



Palla [I.e.) says that this appearance is due to the growth of the two 

 species in a mixed (impure) culture, but that P. sphaerosporus 

 produces its fruit-bodies from one to several days before those of 

 P. Kleinii show themselves. I do not entirely agree with this ; 

 it does not explain the transition stages, which may always be 

 found on looking for them, like those represented by Coemans' 

 intermedia and Klein's variety c of his P. crystallinus, where both 

 ellipsoid and round spores may be seen 

 in the same sporangium. 



Illustration : Fig. 102. The figure 

 here given, from Brefeld's Untersuchungen, 

 is called by him P. oedipus ; it is not 

 that species, but exactly represents my 

 P. Kleinii forma sphaerospora. 



6. Pilobolus heterosporus Palla, Zur 

 Kenntniss der Pilobolus-Arten, in Oesterr. 

 Bot. Zeitschr. vol. 50, p. 349, pi. 10, f. 1-5 

 (1900) ; a Resume of this article, with 

 plates and descriptions, is given by R. Ferr}^ 

 in Revue Mycologique, 1904, pp. 19-33. 



Sporangiophore 2-3 mm. high ; tropho- 

 cyst usually buried in the substratum, 

 ellipsoid, rarely globose, 300-400 fx long. 

 Subsporangial swelhng ovoid or elhpsoid, 

 500-600 fx high, provided at the insertion 

 of the columella with a thin narrow 

 annular zone. Sporangium shaped hke a convex cap, deep-black, 

 400 \i broad ; columella more or less deeply constricted in the 

 middle, rounded at the apex, reaching nearly to the top of the 

 sporangium ; spores yelloA\ or orange-red, varying in form and 

 size in the same sporangium, narrow- or roundish-ellipsoid, 

 with all intermediate forms, 8-20 (or even 25) [x long, and 6-12 [x 

 broad. 



On cow dung, Graz (Styria). 



T have drawn up this description from Palla's rambhng 

 and diffuse account as given in his article. Palla says that he 



Fig. 102. — Pilobolus sphae- 

 rosporus Palla. Fruit- 

 body and spores. 

 Copied by A. H. R. 

 Buller from Brefeld's 

 Untersuchungen (his P. 

 oedipus) and enlarged 

 by one-third. Magnifi- 

 cation, 40 and 400. 



