100 



MOSSES AND FERNS 



CHAP, 



and- these lobes, according to Leitgeb's view, are very simple 

 leaves/ In Fossombronia (Fig. 41, C, D), while the general 

 thallose form is more or less evident, the leaves are unmistak- 

 able, and as their development shows, morphologically the 

 ^me as the leaves of the acrogynous forms. The most re- 

 markable form, however, is Treubia insignis, a very large 

 foliose Liverwort discovered by Goebel in Java. This has all 

 the appearance of a very large acrogynous form, and also the 



typical three-sided apical 

 cell; but in regard to the 

 position of the sexual or- 

 gans it is typically ana- 

 crogynous. These and the 

 Haplomitriese forin a per- 

 fect transition from the 

 Anacrogynae to the Acro- 

 gynse. 



The multicellular gem- 

 mas of Blasia have been al- 

 luded to. They are prox 

 duced in long flask-shaped 

 receptacles, and when ma- 

 ture form nearly globular 

 brownish bodies whose 

 cells contain much oil, and 

 whose stalk consists of a 

 simple row of cells. Among 

 them are glandular hairs, 

 which secrete mucilage, by 

 the swelling of which the 

 gemmae are loosened from 

 their pedicels, as in Mar- 

 chantia. Similar but sim- 

 pler gemmae having usually 

 three cells occur in Treubia 

 (Goebel (13)). Blasia is also characterised by the presence 

 of colonies of Nostoc within the thallus. These occupy cavi- 

 ties in the bases of the leaves and are normally always present.. 



The Haplomitriece 

 The two genera, Haplomitrium and Calobryum, which con- 



FiG. 48. — A, '.Young plant of Aneura pahnata 

 X26S (after Leitgeb) ; B, three views of 

 a young plant of Pellia calycina, X420 

 (Leitgeb). 



