264 
DOUGLAS HOUGHTON CAMPBELL 
definite zone just above the shallow furrow already referred to. The 
writer made no special study of this mycorrhiza which is evidently 
very similar to that found in a number of other liverworts, as well as 
in the gametophytes of a good many ferns, notably the Marattiaceae. 
Goebel discusses at some length the nature of the doisal scales 
which protect the reproductive organs but does not come to a definite 
conclusion. He thinks they may be considered either as independent 
structures, or as part of the leaf. According to Goebel's account, 
which has been confirmed by Griin, the young segment of the apical 
cell, from which this leaf arises, shows, when seen from the surface, 
three cells, of which two give rise to the leaf, and one — that nearest 
the midrib — to this scale. The relation of the leaf and scale is there- 
fore the same as that of the two lobes found in the leaves of so many 
acrogynous liverworts, and it seems to the writer that this is probably 
the simplest interpretation of the case in Treubia. 
Treubia is in several respects much like Fossombronia. This is 
true of the origin of the leaves, and in the position of the archegonia. 
Fossombronia, like Treubia, usually is infested by a mycorrhizal 
fungus — at least this is true for F. longiseta,^ which also shows small 
oil-bodies in some of the leaf-cells. These, however, are much less 
conspicuous than the large oil-bodies of Treubia. Fossombronia 
differs from Treubia in the form of the apical cell,^ which is of the 
two-sided type found in moss Anacrogynae. One of Humphrey's 
figures of F. longiseta,^ suggests the possible occurrence of a three- 
sided apical cell in this species. 
Another liverwort which has the same type of apical cell as Treubia 
is Noteroclada (Androcryphia) , and Schiffner,^ who has studied this 
rare liverwort, concludes that it is nearly related to Treubia with 
which it agrees not only in the form of the apical cell, but also in its 
leaf structure. Schiffner thinks that Noteroclada is also related to 
Fossombronia, with which it is connected by Petalophyllum. 
The Archegonium 
Goebel made no special study of the archegonium, but Grun has 
given a pretty satisfactory account of its most important features, 
^ Humphrey, H. B. The Development of Fossombronia longiseta. Annals of 
Botany, 20. 1906. 
^ Leitgeb, H. Untersuchungen iiber die Lebermcose, Heft iii. Jena. 1877. 
^ Humphrey. L. c. Text-fig. 4, H. 
9 Schiffner. Zur Morphologic von Noteroclada. Osterr. Bot. Zeitschr. 61. 
1911. 
