272 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
sometimes with a single spiral throughout but usually with 2 spirals in the 
median portion for a variable distance. 
Known only from central Mexico; inhabiting damp banks and rocks. The 
following specimens have been examined: 
JaLisco: Near Guadalajara, 1890, Pringle (N. Y., type); Barranca de Ob- 
latos, Guadalajara, Barnes € Land 121 (Y.). 
VERACRUZ: Near Orizaba, Barnes & Land 671 (Y.). 
This interesting and distinct species is still known from very few localities, 
so few in fact that its range of variability may be greater than the description 
implies. The type material in the Underwood Herbarium represents a some- 
what more lax and delicate form than the specimens collected by Barnes and 
Land, but the plants agree closely in their more essential features and there 
is little doubt regarding their identity. Underwood’s original description calls 
attention to the general aspect of the thallus, to the most important charac- 
teristics of the female receptacle and its peduncle, to the white pseudoperianths 
with their coherent segments, and to the dark spores covered over with nar- 
row reticulations, He assigns to the spores, however, a diameter of 118 to 
135 w, which is a trifle high, and states that the elaters have 2 or 8 spirals, 
making no allusion to the fact that they are unispiral at each end and some- 
times throughout their entire extent. He makes no mention, moreover, of the 
various tissues composing the thallus or of the male inflorescence, and his ac- 
count of the ventral scales as “slender whitish [and] lanceolate” omits men- 
tion of the curious teeth which their appendages often show. 
Stephani’s description is somewhat more explicit and supplies some of the 
deficiencies in the original account. He notes the monoicous inflorescence; the 
occurrence of the antheridia on leading branches; the small epidermal pores, 
each surrounded by 6 radiating series of cells with 2 cells in each series; and 
the large hyaline appendages of the ventral scales, sometimes armed with a 
spine. At the same time a few of his statements are open to criticism. He 
describes the branching, for example, as being usually by apical innovations, 
and adds that the female branches always arise from the side of costa. Accord- 
ing to the writer’s observation, apical innovations are rare and the female in- 
florescence is borne on a leading branch produced by forking, agreeing in this 
respect with the male inflorescence. Stephani’s description of the spores as 
“‘ grosse tuberculatae ” is also misleading. 
The ventral scales present several features of interest. The basal portion 
is normally pigmented with purple, but often shows a broad hyaline border. 
Its cells decrease slightly in size toward the margin, but do not show the marked 
increase in irregularity which is usual in the genus; and the slime papillae are 
short-lived and inconspicuous. The small number of cells containing oil bodies 
is also noteworthy. The appendages are remarkable for their large size and 
wide range of variability. At their junction with the basal portion they are 
scarcely constricted, as Stephani notes, and from this rather broad base they 
taper gradually to the sharp-pointed apex. On their sides they may be quite 
entire, but it is not unusual for teeth, irregular in number and in size, to be 
present, and the persistent slime papillae, tipping the teeth or borne directly 
on the margin, represent an ususual peculiarity and stand in marked contrast 
to the short-lived papillae of the basal portion. 
The markings of the spore are likewise subject to great variation: As noted 
in the description, these markings are of two types, the fine lines and the 
coarser folds; and the marked development of one type seems to decrease or 
prevent the development of the other. The type specimens, for example, show 
the folds with especial clearness; these are more or less elongated and show a 
somewhat sinuous course, sometimes being free, and sometimes anastomosing 
