1896] BRIEFER ARTICLES 333 
tion to the host, saying that they are first formed as the result of a 
mechanical stimulus, and that by means of a poisonous secretion they 
injure the tissue, draw nourishment from it, and as soon as this is 
obtained send out branches which for the most part do not pene- 
trate the host directly, but spread over the surface surrounding the 
organ. Later Marshall Ward * described their development, and speaks 
of them as being “of the same morphological nature as those figured 
by Brefeld in Peziza sclerotiorum, and explained by De Bary subse- 
quently as organs of attachment,” while J. E. Humphrey‘ describes them 
as compact cellular masses which cling closely to the surface with which 
they are in contact, but that their real significance is not yet understood. 
—Marcaretua E. C. Horn, University of Michigan. 
EXPLANATION OF PLATE XVII. 
Fig. 1. A branch of an upright hypha bearing conidia. 
Fig. 2. Young developing conidiophore with small projections at a, and 
mature conidia at 6. 
Figs. 3-6. Successive stages of a developing organ of attachment. 
Fig. 7. A prostrate branch bearing mature conidia at @ and a young 
organ of attachment at 4. 
Fig. 8. Hypha entering a leaf of geranium through the stoma. 
ig. 9. Germ tubes penetrating the host between the lamelle of two 
adjacent cells. 
NEW WEST VIRGINIA LICHENS. 
Lecidea Virginiensis Calk. & Nyl., sp. nov.—Thallus glaucescens 
tenuis laevigatus rimulosus citrino-flavus; apothecia fusca aut nigra 
fonvexiuscula immarginata latit. circ. 0.5", intus medio sordida ; 
eft oblonga incoloris, long. 0.009-90.012, Crass. 0.004-6""5 
epithecium et pars media hypothecii dilute fuscescens. In toto gela- 
tina hymenialis coerulescens, dein theca vinose rubescens. 
hy Stirpe videtur Lecidea sanguineo-atra, prope Lecideam delineatam 
On sandstone rock under the drip of a wet cliff. West Virginia, 
hear Nuttallburg, L. W. Nuttall coll. no. 1779. Flora of West Virginia, 
Millsp. & Nutt., 181. 
*Ann. Bot. 2: 327. 18 
7. 1888. ie 
SNj 77 
Ninth Ann. Rept. 1891 and Tenth Ann. Rept. 1892. Mass. Agr. Exp. Station. 
