194 Evans: NOTES ON GENUS HERBERTA 
other respects, the shoots appear almost radial in structure. The 
inflorescence is invariably dioicous. The androecium is at first 
terminal on a secondary stem or one of its branches but soon pro- 
liferates, and the male shoot eventually shows a series of short 
intercalary androecia separated by equally short sections bearing 
normal leaves. The archegonia are likewise terminal on sec- 
ondary stems. When fertilization takes place the growth of the 
female stem is usually brought to an end; when fertilization does 
not take place one or more subfloral innovations may be pro- 
duced. The involucre is composed of crowded bracts and bracte- 
oles, which are essentially alike and not very different from the 
leaves, while the perianth is deeply laciniate at the mouth and free 
or nearly so from the bracts. The calyptra and the sporophyte 
conform to the usual jungermanniaceous type. 
The rhizome of Herberta was apparently overlooked by the 
older writers. Spruce,* however, calls attention to it and to the 
fact that it may bear rhizoids, while Stephani mentions its small 
diameter and copious branching. It tends, in fact, to be con- 
siderably more slender than the secondary stems, although both. 
vary in size. In H. juniperina, for example, an average rhizome 
measures only 0.35 X 0.25 mm. in cross section, while a stem 
measures 0.5 X 0.35. The features of the rhizome are not easily 
made out in material where the secondary stems are well developed. 
The leaves are more or less disintegrated with age and it is dif- 
ficult to demonstrate the relationship between the branches and 
the leaves. In most cases the leaves and underleaves are minute 
and widely separated. The leaves are practically transverse in 
their insertion and it would be difficult to distinguish them from 
the underleaves, if the rhizome did not show a slight dorsiventral 
flattening, the underleaves being of course situated on one of the 
flattened sides. Both leaves and underleaves are distinctly bifid. 
The rhizoids grow out normally from the basal cells of the under- 
leaves, although they often occur on the leaves as well, but the 
rhizome itself is usually free from them. The branches are all — i 
intercalary and many of them spring from the axils of the under- 
leaves. This position, however, is not constant; occasional 
branches tend to be lateral and do not show a definite relationship _ 
* Trans. Bot. Soc. Edinburgh 15: 340. 1885. 
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