1920] Holm,—Internal Glandular Hairs in Dryopteris 89 
MISCELLANEOUS SPECIES. 
Athyrium angustum Thelypteris Boottii 
Thelypteris spinulosa, var. concordiana 
Athyrium angustum, the dimorphic sun form of the lady-fern 
group, seems to be absent from large areas, for no obvious reason, 
unless that it has not been collected in sufficient quantity as yet. 
Thelypteris Boottii, now generally regarded as a hybrid between 
T. cristata and T. spinulosa, var. intermedia, is well distributed but 
seldom abundant. It seems to prefer swampy places in rich woods 
areas, but is not reported from northern Maine and northern New 
Hampshire, nor from Rhode Island. T. spinulosa, var. concordiana 
was discovered by Henry A. Purdie and William Brewster at Con- 
cord, Mass., in 1902 (Ruopona vi. 313. 1904), and is as yet known 
certainly only from the type locality. 
C. H. KNOWLTON, 
W. S. RiPLEY, JR., 
C. A. WEATHERBY. 
INTERNAL GLANDULAR HAIRS IN DRYOPTERIS. 
Taero. Horm. 
ANATOMICAL studies of the ferns reveal many points of interest, 
and especially with regard to the arrangement of the various tissues 
in the stem and stipe. Moreover it is in the ferns that internal, 
glandular hairs have been observed, and such are described by De 
Bary! as characteristic of Dryopteris Filix-mas, and D. spinulosa. 
These hairs were found in the ducts of the rhizome and the base of 
the petiole. Another type of internal hairs is known from Pilularia, 
Nymphaeaceae, Araceae, Rhizophora and Limnanthemum, but these 
hairs are not glandular. 
Concerning the presence of these hairs in the ferns it does not seem 
that they have been found in the leaf except in the petiole, nor have 
they been recorded from any of the other species of Dryopteris, nor 
from other genera. Some few years ago, when engaged in studying 
the anatomy of some of our ferns from living specimens, I found these 
hairs in the intercellular spaces of the leaf-parenchyma in Dryopteris 
! Vergleichende Anatomie der Vegetationsorgane der Phanerogamen und Farne. 
Leipzig, 1877, p. 230. 
