700 ADDITIONAL EXERCISES 



14. Large species 6 to 8 cm. tall (exceeding in all cases 2 cm.). (15) 

 Small species never exceeding 2 cm. in height. (16) 



15. Sporangiophores 6 to 7 cm. in height, sporangia 300 to 400/1 (exceptionally 

 Soo;j), spores 7.5 by 17-5*'. 25 .1/. proliferus Schostakowitsch. 

 Sporangiophores 6 to 8 cm. in height, sporangia 140 to 150^1 diameter, 

 spores 4-2/1 by 9 to i2ix. 26 M. fla-etis Bainier. 



16. Columella largely subjacent and concrescent with the wall of the sporangium, 

 diameter loo/i, spores 2 to 4/1- 27 J/, mollis Bainier. 



Columella free and slightly flattened at base. (17) 



17. Spores oval, small i.ifi by 4.2/1, a grayish-blue. 28 M. JragUis Bainier. 

 Spores elongated plano-convex, unequal, 2 to 5/1 by 5 to lo/i. (18) 



18. Sporangia never exceeding 80/1, zygospores frequent, forming (on bread) 

 special branches. 2g M. generensis Lendner. 



Sporangia a mean of 80/1 frequently 120/1 diameter, suspensors bearing the 

 sporangiophores as with M. racemosus (Fig. 30). 30 M . erecltis Bainier. 



3 Group — Cymo-Mucor 



Sporangiophores branched in sympodial cymes. 

 I. Sporangiophores of two kinds, the one straight and bearing the normal 



spheric Sporangia, the other creeping, cirdnate branches sympodial. bearing 



piriform sporangia. 31 M. pirelloides Lendner. 



Sporangiophores of a single kind. (2) 

 ^. Sporangiophores cirdnate. (3) 



Sporangiophores straight not drdnate. (6) 



3. Sporangiophores never exceeding i cm., spores oval, ma.ximum length 6/«. (4) 

 Sporangiophores exceeding i cm. sometimes 3 cm., spores spheric, lo/i or 

 more. (5) 



4. Wall of sporangium brown, sporangium frequently subsessile, spores 3 to 

 4/1 by 5 to 6/1 long. 32 .1/. circinelloides van Tieghem. 



Sporangia wall bluish-black, sporangia carried on long pedicels, frequently 

 circinate, spores 4/1 by 5 to 6/1. 33 ^t. griseo-cyanus Hagem. 



5. Sporangiophores creeping, J2 to 2 cm., sporangia black 120 to 200/1, spores 

 10.5/1 to 14/1 in diameter. 34 M. angariensis Schostakowitsch. 

 Sporangiophores straight not circinate, the others short, freely branched and 

 cirdnate, sporangia small 60/1 (mean), 12/1 (ma.ximum). 41 M. lamprospcrus 

 Lendner (Fig. 242). 



6. Spores spheric or very unequal of diverse forms. 35 M. heleros poms sibirkus 

 Schostakowitsch. 



Spores spl^ric appreciably equal. (7I 

 Spores oval. (12) 

 7- Species poorly cultivated on grape-juice gelatin, forming on bread a short 

 mat of 2 to 3 ram., sporangia 50 to 70/1, spores spheric, 5 to 6/1. 36 if. 

 Jansseni Lendner. 



Species readily cultivated on grape-juice gelatin, forming a taller matted 

 surface (i to 3 cm.). (8) 



