192 .. BOTANICAL GAZETTE [MARCH 
LisT OF SPECIES OCCURRING IN EUROPE ONLY 
Acremoniella pallida Cooke and Mass., Actinonema Ulmi 
Alleschr., Ascochyta ulmella Sacc., Asteroma angulatum Desm., 
A. Fuckelit Sacc., Cladosporium hypophyllum Fuck., Exoascus 
campester Sacc., Gloeosporium inconspicuum Cav., G. inconspicuum 
Cav.. var. campestris Dor., Laestadia comedens (Pass.) Sacc., 
Pestalozzia maculicola Rostr., Phyllosticta bellunensis Mart., 
P. lacerans Pass., P. ulmaria Pass., P. Ulmi West., Sphaerella 
Oedema (Fr.) Fuck., S. insularis Wallr., Sphaeria ulmifolia Pass., 
Sporodesmium Ulmi Fuck., Stagonospora ulmifolia (Pass.) Sacc., 
Stigmella Castagneana (Mont.) Sacc., and Taphrina Ulmi Johans. 
FOSSIL LEAF SPOTS OF ELM 
In MESCHINELLI’s Fungorum Fossilium Iconographia seven 
species are given occurring on leaves of fossil elms. Plates and 
figures are included for six of these, but they are very unsatisfac- 
tory in most cases, and in some instances one cannot be at all sure 
that the spot is even of fungal origin. The species are as follows: 
Sphaerites perforans Goepp., S. glomeratus (Engelh.) Mesch., 
S. rhytismoides (Ettingsh.) Mesch., Rhytismites ulmicola (Ettingsh.) 
Mesch., R. Ulmi (Ludw.) Mesch., Depazites Ulmi (Ettingsh.) 
Mesch., and Xylomites sp. (Boulay) Mesch. 
Summary 
1. Gnomonia ulmea (Schw.) Thiim., the cause of the most 
common elm leaf spot in America, has been reported as occurring 
on five of the six native species of elm in this country and is of 
wide distribution, being found throughout the entire range of its 
hosts. Its normal host, on which it is most commonly found, is 
Ulmus americana. The fungus is not ordinarily of much economic 
importance, but may cause considerable injury to seedlings and 
young trees in nurseries by producing premature defoliation. 
2. Unlike most of the Ascomycetes, the perithecial stage of 
the fungus begins its development in the living leaf early in the 
spring. The young perithecium develops in the palisade tissue 
beneath a subcuticular black stroma. 
3. An ascogonium is found in the young perithecium, but 
there is no trichogyne. 
