1900] Merrill, — Occurrence of Thamnolia in Maine 155 
unreasonable to interpret them as reversions to a primitive type of 
Sagittaria. That prototype may have been a submerged plant. 
THE AMES LABORATORY, North Easton, Massachusetts. 
EXPLANATION OF PLATE 19. Figure 1, a growing seedling of Berberis vu'garis. 
2, characteristic leaf of the same species. 3, a pressed seedling of B. Zhunbergii, 
4, reversionary leaf common on BZ. repens. 5, one of six very large, 3-foliolate leaves 
on a sucker-like shoot of B. repens. 6, the character leaf of the same species. 
7, stages in the development of Sagittaria AMontevidensis: a, b, c, d, e progressive 
forms; the character leaf, sagittate, not represented; f, g, Å regressive forms in ex- 
hausted shoots. 
THE OCCURRENCE OF THAMNOLIA IN Mampg, The rare alpine lichen 
Thamnolia has not before been reported from Maine, and the following 
note may be of interest. In August, 1896, the writer collected near 
the summit of Mt. Washington, New Hampshire, the typical form of 
Thamnolia vermicularis (Sw.) Schaer.; and in September, 1898, an 
interesting form of the same species was found near the summit of 
Mt. Katahdinin Maine. Specimens of the latter form were sent to Miss 
Cummings, who determined them as Zhamnolia vermicularis, var. 
subuliformis Schaer., and stated that in the Tuckerman Herbarium 
there was but one representative of the type. 
In habit of growth the variety is strikingly different from the type, 
this feature being more marked than the shape of the thallus. The 
type as collected on Mt. Washington was growing in densely cespitose 
bunches, and the variety, as on Mt. Katahdin, was not at all cespitose, 
but was very scattered, often isolated and intermixed with other lichens 
and mosses, notably with Cetraria /slandica. It was found only spar- 
ingly, and no specimens of the typical form were observed. 
This species resembles at first sight a dead or bleached form of 
some o the alpine species of Cladonia, but its color is very distinctive. 
Owing to its silvery gray shade and its subulate thallus it is a very 
beautiful and striking species. — ELMER D. MERRILL, Washington, D. C. 
ASPIDIUM SIMULATUM IN NEW HAMPSHIRE. — Aspidium simulatum 
was illustrated and described by Mr. George E. Davenport in the latter 
part of 1896. Since that time it has been reported from compara- 
tively few stations over a wide range. The writer is not aware that 
this fern has been reported from but two localities in New Hampshire, 
namely, Seabrook and Kingston. These towns are in close proximity, 
