306 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
white to purple and the number of divisions from 8 to 12. With regard to the 
shape of the female receptacle the difference betwen “ subconoidal” and “ sub- 
hemispherical” is certainly slight; Stephani, in fact, speaks of the receptacle 
in A, violacea as having an “alte rotundato” center and of that in A, bo- 
landert as being ‘“ hemisphaerica,” and thus seems to imply an even slighter 
difference, The difference in the direction of the lobes is sometimes striking 
but by no means constant. In Howe’s plate 98, figure 4, the typical condition 
of A. violacea is seen, the lobes being directed downward rather than outward, 
but in figures 5 and 6 the lobes spread about as much as in plate 97, figure 7, 
where a typical receptacle of A. bolanderi is depicted. On the whole, these 
slight differences in color and in shape, as well as in the size of the receptacle, 
are paralleled by other species and might easily be caused by differences in en- 
vironment. 
The difference in the size of the spores is perhaps deserving of more consid- 
eration and is usually accompanied by a difference in the width of the marginal 
wings. In a series of specimens labeled A. violacea the spores measured 80 to 
110 » in diameter, and the wings were 10 to 16 mu or even as much as 20 yw in 
width ; in a series labeled A. bolanderi, the spores were mostly 65 to 70 wu (rarely 
80 «) in diameter, and the wings were rarely 12 » in width. The difference 
in the width of the elaters was less apparent: in A. violacea it was usually 
10 to 12 yw, although sometimes only 8 »; in A. bolanderi, it was mostly 8 to 
10 w. At the same time, it should be emphasized that the spore Markings, as 
shown by Howe’s descriptions and figures (pl. 97, f. 21; pl. 98, f. 13), are es- 
sentially the same, whatever the size of the spores, Even the difference in size 
of the spores, however, is insufficient to be considered specific, since it is un- 
supported by other trustworthy characters. An equally great variation in size 
is found in other species of Asterella and also in other genera of the Opercu- 
latae. In Reboulia hemispherica, for example, Schiffner' distinguishes a variety 
microspora, in which the spores have a diameter from one-fifth to one-fourth 
smaller than those of the typical form. Associated with this difference in size 
he finds a difference in color, the spores of the variety being much paler, and 
he finds similar variations in color in the spores of Targionia, Grimaldia, and 
Neesiella, Without attempting to explain these variations in all cases he sug- 
gests that a small size and a pale color may sometimes be due to immaturity, 
and he warns against the practice of placing too much reliance on such devia- 
tions from type in the proposal of new species. The writer therefore feels 
justified in regarding A. violacea as a synonym of A. bolanderi., 
When Howe published A. lateralis as a new species he regarded it as an ally 
of A. bolanderi, largely on account of its short ventral sexual branches. In 
distinguishing it he emphasized the spore differences, the somewhat smaller 
female receptacle, the 8-cleft pseudoperianth (10 to 12-cleft in A. bolanderi), 
and the shorter and broader elaters. If A. lateralis is defined in the broad 
sense indicated in the present paper, the spore differences are not very strik- 
ing, the markings being much alike in the two species, except that in A. later- 
alis the wings rarely take part in the formation of the reticula and the meshes 
tend to be a little larger. The differences in the size of the receptacles is like- 
wise slight, if well-developed specimens are compared. The other differences men- 
tioned by Howe are more significant, and it may be added that the elaters of 
A. lateralis tend to be unispiral for a longer distance than those of A, bolanderi. 
The longer tubercles on the receptacle of A. lateralis afford another distinctive 
feature; in A. bolanderi the tubercles are very short or even lacking altogether, 
the surface appearing smooth. In some respects A. lateralis occupies an inter- 
*Oesterr, Bot. Zeitschr, 58: 228. 1908. 
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