972 
forms, and pointing out the great need of fur- 
ther observation to clear up doubtful points in 
their reproductive processes. 
President Brown exhibited specimens found 
by Dr. Meredith at Danville, Pa., of Ajuga 
Genevensis and of Hieracium Pilosella. The first 
had been observed on ballast in New York 
City, but not the latter. 
On December 12th, the scientific program 
was opened by a paper by Dr. L. M. Under- 
wood ‘On the Genera of the Schizaeaceae.’ 
Dr. Underwood explained the peculiar detri- 
scence of the sporangium by which this order 
of ferns is distinguished, illustrating with fig- 
ures, and then sketching the history of the 
order. Linnzeus put its species under Acrosti- 
chum ; Richard was the first to begin segrega- 
tion, erecting in 1792, the genus Lophidium. 
In 1708, Schizaea was founded by Smith, on a 
South African plant common through the 
Transvaal region, quite closely similar to our 
own species of New Jersey. Wallich founded 
another genus, Actinostachys, in 1822, on an 
East Indian form. Dr. Underwood considered 
these three genera to be valid, though recent 
German systematists, as Prantl, have not 
recognized them. 
Swartz constituted another genus in 1800, 
Mohria, from Cape Colony, of which only one 
species is known. Lygodium, our best known 
genus, was established by Swartz in 1800, and 
includes one well known Atlantic species, 
L. palmatum, the climbing-fern. 
Several other genera, as Aneimia and Tro- 
chopteris, were discussed, with remarks on 
principal species. About 90 species of the 
order have been published, largely American 
and tropical, especially the abundant Brazilian 
forms of Aneimia and allies. 
Professor Lloyd suggested the interest at- 
taching to .Trochopteris as possibly a very 
primitive fern. 
Dr. Underwood said it is sparsely represented 
from Brazilian collections, but perhaps because 
of its small size and habit of growth close to 
the ground, the largest specimen known being 
only three inches in diameter. 
The second paper was by Dr. D. T.* Mac- 
Dougal, ‘Studies on Hexalectris.’ This rare 
southern orchid is of great interest on account 
SCIENCE. 
[N. 8S. Von. X. No. 261. 
of its supposed near relationship to Corallorhiza, 
which develops short coralloid undergrowths 
without roots, but producing a mycorhiza and 
sending out hyphz into the soil. Material of 
Hexalectris from Alabama although possessed 
of somewhat similar coralloid growths, was 
found to contain no fungi, and to be without 
apparent adaption to growth by mycorhiza. 
No one seems to have seen seen the roots of this 
plant. . 
The third paper was by Dr. N. L. Britton, 
‘Notes on Species of Crataegus.’ 
Dr. Britton exhibited and discussed 34 species 
of the northeastern United States and remarked 
upon the great need of persistent field study 
in determining this genus. One must have 
flowers, mature leaves and mature fruit from 
any individual bush before he can begin to find 
its relationship to any other form. The most 
difficult part of the genus is perhaps the @. 
tomentosa group. Many southern species have 
recently been found to extend their range into 
Virginia, as C. Chapmani, C. Carolina, ete. ; 
and others in Missouri, as C. berberifolia. The 
identity of the original of C. coccinea of Linnzeus 
proves to have a special local interest. Lin- 
neeus seems to have had, as often, no specimen 
before him, but based his description on a plate 
of Plukenet (and another of Ray). Few her- 
barium specimens correspond well to the figure, 
which answers only to leaves of a shrub col- 
lected twice near New York, once by Mr. E. 
P. Bicknell along the Harlem River and once 
by the late Professor E. H. Day on Persimmon 
Island near New Rochelle, New York. The 
leaves bear a remarkable resemblance to those 
of Betula nigra. Search for similar specimens 
near New York should be made; the leaves are 
longer and with blunter, shallower lobes than 
in the commonly-received C. coccinea. 
Dr. Britton is endeavoring to get together at 
the Botanic Garden a collection of these species, 
and now has over a dozen; but the wild stock 
is very difficult to grow and is impatient of 
transplanting. Most gardeners graft or grow 
from seed. 
After discussion by Dr. Rydberg, President 
Brown and others, the Club adjourned. 
EDWARD S. BURGESS, 
Secretary. 
