1916] Evans, — Notes on Xew England Hepaticae,-^ XIII 105 



form and relative width of the lobule could hardly be improved upon, 

 but here again the margin is not invariably entire as he maintains. 

 A very few minute and irregular teeth may be present along the inner 

 edge (especially when this is slightly decurrent) and also close to the 

 jmiction with the lobe, where the lobule is more or less dilated. 



Miiller's description of the leaf-cells and underleaves portrays very 

 accurately the conditions which are present in the material studied 

 by the writer. On account of the strongly arched line of attachment of 

 the underleaves the decurrent portion is vaguely delimited from the 

 portion which is not decurrent, but in any case the decurrence is 

 strongly marked. 



His account of the perichaetial leaves, however, deserves a little 

 amplification. The two bracts are usually unequal in size, the one 

 (see Fig. 7) which is turned toward the apex of the axis bearing the 

 female branch (that is, the outer bract) being the smaller of the 

 two. Although the lobe and lobule are frequently of about the same 

 size, it is more usual for the lobe to be distinctly larger than the lobule 

 (see Figs. 7, 8), and the apices of both lobe and lobule A'ar;^- from acute 

 to obtuse or even rounded. Marginal teeth are sometimes absent but 

 this is by no means invariably the case. In some of the bracts exam- 

 ined both lobe and lobule bore a number of scattered irregular teeth, 

 some of which were little more than projecting cells while others were 

 larger and more lobe-like. In connection with some of the teeth 

 vestiges of slime papillae could be discernetl. Similar teeth are some- 

 times present on the perichaetial bracteole (Fig. 9). 



In European specimens of P. platyphyJla the mouth of the perianth 

 with its scattered teeth (Fig. 10) presents a very distinctive appear- 

 ance. Each lip usually bears from fifteen to twenty teeth, and the 

 teeth themsehes vary from single projecting cells to cilia four or five 

 cells long and one cell wide throughout or to triangular teeth as long 

 as such cilia but three or four cells wide at the base. The teeth are 

 exceedingly fragile, and their peculiarities cannot always be made out 

 from old and weathered perianths. P'ortunately the perianth starts to 

 develop even when no archegonia are fertilized and, since the mouth is 

 the first part to mature, the unrleveloped perianths dissected out from 

 unfertilized infiorescences will usually show the marginal teeth clearly. 



In the North American specimens which the writer would refer to 

 P. plati/phi/Ua the teeth show a tendency to be more crowded than in 

 the European specimens, a condition which Figs. 11-14 clearly bring 



