322 Alexander W. Evans, 



at the apex. Sometimes, except for this apical tooth, the margin 

 is quite entire, but it is much more usual for the lobe to bear from one 

 to five supplementary teeth in the vicinity of the apex. These teeth 

 tend to be more numerous along the antical margin, but some of them 

 are occasionally situated on the postical margin. In most cases 

 the apical tooth is distinctly larger than the others, but this is not 

 always the case, the antical tooth next the apex sometimes approach- 

 ing or equalling the apical tooth in size. Under these last circum- 

 stances the apical tooth is less conspicuous than on most leaves. 



The true lobular features can not always be made out without dis- 

 section. If this is done the lobules are found to conform pretty 

 closely with Spruce's description, although it should be noted that 

 neither he nor Stephani makes any mention of the proximal tooth. 

 The apical tooth of the lobule is short and rather sharp, being tipped 

 by a single cell or by two superimposed cells; in other words it is 

 usually two cells long and one or two cells wide at the base (Fig. 7, 

 D, E). Just below the tooth four or five cells are usually connected 

 with the basal cell or cells. The proximal tooth is short and consists 

 of httle more than a single projecting cell. Apparently trigones are 

 always present, but they may be very inconspicuous with conca\^e 

 sides. Even when better developed they are less striking than in 

 most members of the Lejeuneae Holostipae. 



With regard to the inflorescence it is extremely difficult to demon- 

 strate antheridia or their vestiges after the sperms have been set 

 free and especially after perianths and sporophytes have developed. 

 It is only on very young fertile shoots, where the innovations have 

 just begun to grow, where the archegonium is still unfertilized, 

 and where the perichaetial bracts and bracteole are only partially 

 developed, that the antheridia show clearly. In typical cases there 

 about eight pairs of perigonial bracts just below the female inflor- 

 escence. As might be expected delicate and etiolated plants some- 

 times develop antheridia but no archegonia. This is shown particu- 

 larly well in material collected by A. Stewart on Albemarle Island, one 

 of the Galapagos group. In some plants from this collection certain 

 stems or leading branches bear a series of perigonial bracts and then 

 continue their growth as ordinary vegetative shoots. This may 

 perhaps be considered an example of reversion, due to the fact 

 that the conditions are not very favorable for the development of 

 reproductive organs. 



Spruce's description of the perianth and bracts (Fig. 7, F— L) is 

 unusually full and accurate. The postical keel of the perianth, as 

 he remarks, is low and usually smooth. But this appearance is not 



