BIOLOGIC SPECIALIZATION IN THE GENUS SEPTORIA 
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Specialization. But since the forms have been proved to be different both 
morphologically and biologically, they should each have specific rank. 
The name S. convolvuli is reserved for the form on Convolvulus sepium upon 
Diagram 8. Infections with Septoria verbascicola from Verbascum hlattaria. 
which host the type of S. convolvuli was described (6) . For the form upon 
Convolvulus arvensis the following new species is proposed : 
Septoria septulata sp. no v. 
Spots orbicular, then irregular and confluent, light brown to dark brown; 
pycnidia mostly epiphyllous, innate, globose, 60-90 protruding with a 
prominent ostiole, 20-30 /x; spores curved or flexuous, one end narrow with 
a more acute tip, 3-5 septate, 30-50 fx long by 1-2 ju wide. Habitat : old or 
fading leaves of Convolvulus arvensis. 
This species appears to be the equivalent of the form on C. arvensis 
described in Saccardo's Sylloge Fungorum, 3: 536. 
Septoria verbascicola Berk. & Curt. 
Septoria verbascicola appears to be somewhat adaptive in its host rela- 
tions. The infection of Scrophularia marilandica was as vigorous as that 
on the original host when conditions were made favorable for the fungus. 
This was done by keeping the inoculated plant constantly covered with a 
bell jar for ten days, and by atomizing the leaves daily with water following 
the application of the spores. At the end of this period under cover disease 
