270 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Bryophyta. 



Studies on some East Indian Hepaticae. — D. H. Campbell 

 {Annals of Botany, 1918, 32, 319-38, 2 pis. and figs.). An 

 account of the structure of Dumortiera trichocephala, D. velutina, 

 D. calcicola (a new species from Sarawak, Borneo), and of Wiesnerella 

 denudata, with special attention to the reproductive organs, the carpo- 

 cephaluni, the sporophyte. The most striking peculiarity of Dumortiera 

 — i.e. the more or less complete obliteration of the air-chambers — is 

 secondary and associated with the marked hygrophilous habit of most 

 of the species. Of the species examined, D. velutina shows the least 

 reduction, for not only are the outlines of the air-chambers quite 

 evident, but the characteristic assimilative tissue is present in the form 

 of very numerous superficial papillate cells. In D. trichocephala, which 

 is more strongly hygrophilous in its habit, the reduction of the air- 

 chambers is much more complete, and in one Hawaiian species (assumed 

 to be D. trichocephala) the suppression is complete, as it is in the pre- 

 sumably related genus Monoselenium. Wiesnerella is especially interest- 

 ing, as it is on the one hand unmistakably closely related to Dumortiera, 

 while on the other it is obviously connected with the typical Marchan- 

 tiace^e. It may be fairly said to connect forms of the type of Marchantia 

 with the reduced Dumortiera. Almost the only evidence of reduction 

 in Wiesnerella is the character of the stomata, especially those of the 

 receptacle. A. G. 



Androecium in Plagiochasma appendiculatum L. et L. and 

 P. articulatum Kashyap, — S. R. Kashyap {N'ew Phijtologist, 1919, 

 18, 235-8, 2 figs.). Three different considerations are put forward 

 to show that the androecium of P. appendiculatum and P. articulatum 

 is really homologous with that of the higher Marchantiales in being a 

 branch-system. The dorsal position, like the dorsal position of the 

 female receptacle, is quite secondary, as has already been shown by the 

 author {Op. cit. 13, 9). In P. articulatum the androecium is quite 

 terminal at first. The three considerations are : — (1) The arrangement 

 of the scales at the tip of the lobes, very similar to that at the tip of 

 the vegetative lobe ; (2) the repeated branching of the receptacle, two 

 or three times in some specimens ; (3) the invariably acropetal succes- 

 sion of the antheridia in all lobes exactly as in Marchantia, the highest 

 genus of the Marchantiales. A. Gr. 



New Moss from the Pleistocene of Kecskemet, Hungary. — 

 K. ScHiLBERSZKY {Math. u. naturw. Ber. Ungarn., 191-4, 2, 167-77, 

 5 pi., text figs.). The moss here described was found at a depth of 

 35 m., on boggy land near Kecskemet, among various plant remains. 

 The stratum belongs to the Pleistocene age. It differs from any existing 

 species of Bypnum, and is called H. Holloscicmum after the finder. Its 

 closest allies are H. Schreberi and H. cuspidatum. Comparison is drawn 

 between it and H. Taramellianum, which is also described in detail. 

 Figures are given reproducing the habit of both these species, and the 

 structure of H. Holloscianum. E. S. G. 



