Holzingcr : MUSCI OF THE INTERNATIONAL BOUNDARY. 45 



malia collected by Professor James, near Franconia, N. 

 H., named H. jamcsii Schimp., and probably typical 

 material of Schimper's species, also with H. trichoman- 

 oldcs from Denmark, collected by Dr. J. Hensen, near 

 Hvako, in 1883 ; and I fail to find a single good reason 

 for separating our American forms of Homalia with ser- 

 rate leaves from the European Homalia trichomanoides 

 as a distinct species. Not a single constant character 

 can be established for our plant. I have made microm- 

 eter measurements of the leaf cells of all the specimens 

 examined, and I find them essentially of the same size 

 in the same part of the leaf in all specimens. The 

 American specimens that are fertile show not the slight- 

 est difference from European specimens either in peri- 

 chastial leaves or in perforation of the segments of the 

 peristome along the keel. The only point of difference 

 is the, on the whole, more obtuse apex of the leaves in 

 our American forms. But it cannot fail to attract the at- 

 tention of the student, especially when he reviews a large 

 number of forms in different collections, that while in 

 our American forms the apex is on the whole more 

 rounded, some leaves may be found on every plant which 

 have an apiculate apex. Also the European plants 

 studied show some leaves more rounded at the apex than 

 others. As for the description of the European plant, 

 by European authors themselves, let me cite first from 

 Muscinees de la France by M. PAbbe Boulay (1884), p. 

 150. " Feuilles largement oblongue-elliptiques, con- 

 vexes-cultriformes par le bord superieur, un peu repliees 

 en dessus par 1'inflexion du bord inferieur, brevement 

 apiculees, tres finement denticulees sur tout le contour 

 (dont plus grandes et plus rapprochees ver le sommet ; 

 long. 2, larg. i mm. ***** cellules moyennes 

 8-10 fois aussi 1. q. 1. ; vers les bords et au sommet, elles 

 sont courtes, rhomboidales ; * * * * lanieres 



du peristome interne lineares, plus longues que les dents, 

 peu ou millement ouvertes ver la carene." 



InLimpricht'sLaubmoosell (1895), p. 715: "Blatter 

 gedrangt, zweizerlig-abstrehend, zuletst abwarts gebo- 

 gen, flach ausgebreiten, unsymmetrisch, aus herablaufen- 

 der, etwas verschmalerter Bariszungen-messerformung, 



