154 IMPORTANT VARIETIES OF FISSION-FUNGI. 



potato growth chrome-yellow, glistening ; no large regular bales of 

 packets formed. Sarc. flava de Bary, emend. Lehmann and Stuben- 

 rath, page 159. 



(6) Gelatin plate magnified sixty times; medium-sized granules ; 

 beautiful regular bales of packets formed. This group contains transi- 

 tions from flava to lutea, and from the yellow to the white forms. 



() Potato growth ; at first dark gray, only later yellowish-brown. 



Sarc. livido-lutescens Stubenrath, page 159. 

 (/?) Potato growth ; from the beginning grayish-yellow, at other 



times very similar. Sarc. equi Stubenrath, page 158. 

 (y) Like Sarc. equi, but motile from long flagella, sometimes 



somewhat fluorescent. Sarc. mobilis Maurea, page 160. 

 (c) Gelatin plates magnified sixty times are coarsely granular. 

 Formation of beautiful regular bales of packets ; potato growth, from 

 beginning, luxuriant lemon-yellow. Sarc. lutea Fliigge, emend. 

 Lehmann and Stubenrath, page 157. 



III. UPON AGAE AND GELATIN ORANGE- YELLOW. Sarc. auran- 

 tiaca Fliigge, page 160. 



IV. UPON AGAR AND GELATIN BROWNISH TO BROWNISH-YELLOW. 

 (a) Agar streak succulent, broad, reddish-brown. Sarc. cervina 



Stubenrath, page 162. 



(&) Agar streak thin, finely notched, and furrowed, yellowish- 

 brown, transparent. Sarc. fulva Stubenrath, page 156. 



V. UPON AGAR AND GELATIN BRIGHT ROSE-RED. 



(a) Gelatin and agar streak rose-colored ; sarcina form observed only 

 upon hay decoction. Sarc. rosea Schroter, emend. Zimm., page 162. 



(6) Gelatin and agar bright red ; sarcina form observed by us only 

 once upon hay decoction. Sarc. erythromyxa Krai, page 162. 



That it will always be possible to distinguish the 

 ' ( forms ' ' presented in the key, we can not certainly claim, 

 since in spite of the observation during two years of very 

 numerous forms, we have reached no final judgment con- 

 cerning the extent of variability and perhaps the occur- 

 rence of transition forms. 



Leaving the chromogenesis out of account, we can cite 

 at least two striking examples of their variability (com- 

 pare Sarc. variabilis and mobilis); thus, the following 

 appears the natural relationship: 



1. Sarcina flava, therefrom is the white form, Sarc. 

 alba. 



2. Sarcina equi, therefrom is the white form, Sarc. 

 canescens. 



Between equi and canescens Sarc. livido-lutescens and 

 Sarc. variabilis reestablish a connection. 



The varieties Sarc. flava, equi, and lutea form a series 



