724 ADDITIONAL EXERCISES 



Key to Species of Microsph^ra (After Salmon) 



Brief Characterization. — Perithecia globose to globose-depressed; asci several, 

 two- to eight-spored. Appendages not interwoven with the mycelium, branched 

 in a definite manner at the apex, which is usually several times dichotomously 

 divided, and often very ornate, rarely {M. astragali) undivided, or once dichotomous 



1. Asci two-spored, appendages densely crowded, flaccid, about equalling the 

 diameter of the perithecium. 6 Mougeottii. 



Asci more than two-spored. (2) 



2. Appendages two and one-half to seven times the diameter of the perithecium, 

 usually much contorted and angularly bent, apical branching very irregular 

 and lax, with the branches very flexuous and more or less curled. 9 euphorbia. 

 Appendages long or short without the above characters. (3) 



3. Tips of some or all of the ultimate branches of the appendages recurved. (4) 

 Tips not recurved. (11) 



4. Appendages eight to twelve times the diameter of the perithecium. 10 

 Guarinonii. 



Appendages less than eight times the diameter of the perithecium. (5) 



5. Appendages long and flaccid. (6) 



Appendages short, not exceeding two and one-half times the diameter of the 

 perithecium, not flaccid. (8) 



6. Apex of appendages much branched, branching ornate, more or less close 

 spores 22 to 26 by 12 to iS/x. 4 alni var. extensa. 



Apex less branched, more or less widely, forked, or branching close and simple, 

 spores 18 to 23 by 9 to 13M. (7) 



7. Appendages usually three and one-half, not exceeding five and one-half times 

 the diameter of the perithecium, asci three to seven, ovate-globose, 38 to 

 48ju long. 4 alni var. divaricata. 



Appendages two and one-half to eight times the diameter of the perithecium, 

 asci two to sixteen, ovate-oblong, 45 to 72/i long. 4 alni var. vaccinii. 



8. Appendages more or less contorted, apical branching very lax and irregular. 

 4 alni var. liidens. 



Appendages not contorted, apical branching closer and regular. (9) 



9. Tips of the ultimate branches of the appendages not all regularly and dis- 

 tinctly recurved. 4 alni var. lonicera. 



Tips all regularly and distinctly recurved. (10) 



10. Axis pf some of the appendages not dividing dichotomously at the apex, but 

 bearing sets of opposite branches. 4 alni var. calocladophora. 

 Appendages regularly dichotomous at apex. 4 alni. 



11. Appendages three to seven times the diameter of the perithecium, colored 

 nearly to apex. 8 Russdlii. 



Appendages colorless. (12) 



12. Appendages long and penicillate. (13) 

 Appendages not penicillate. (15) 



