26 Bryophyten. — Floristik etc. 



System, in which dichotomy occurs rapidly, and the several growing- 

 points formed are of short-lived activity. 3. The bivalved involucre 

 developes simultaneously with the archegonial group, and represents 

 the peripheral region of the archegonial surface, but its further 

 growth, the formation of interlocking processes on its margin, and 

 its closure until the extrusion of the capsule, are dependent on the 

 occurrence of fertilization in one or more of the archegonia. 4. The 

 young sporogonium does not show the octant stage usually regarded 

 as characteristic of Marchantiales, but approaches the '' Jungerniamiia 

 type", a row of cells being formed by successive transverse divisions 

 before the first longitudinal divisions occur. The spore mother cells 

 and the elaters occur in approximately equal numbers, and are. 

 irregularly mingled, but there is invariably a layer of elater forming 

 cells immediately within the Single layered capsule wall, and these 

 cells maj^ either remain attached by their entire length to the 

 inside of the capsule wall, or by one end on\y\ in the former case 

 making the wall two-layered in places, in the latter case forming 

 fixed elaters. A. Gepp. 



Stirton, J., Additional Mosses from Duncraig, West 

 Ross-shire. (Trans. Proc. Bot. Soc. Edinburgh. Vol. XXVI. 

 Part IV. p. 423-429. 1915.) 



The author discusses iive species of Leptodontiuni found in 

 West Ross-shire. L. flexifoUmn , L. recurvifolinm and L.getnmascens 

 have been known for some years; but he is of opinion that the 

 last named species should be excluded from the group. L. terrenuni 

 was described by him in 1900; and now he adds a fifth species, new 

 to science, L. Rossii. He also describes Campylopus obtectus n. sp., 

 Lhnneria (gen. nov.) viridtila n. sp., Bryiim intortiüu'ni . Limneria 

 approaches in some respects Rhacomitriinn and Canipylosteliuni. 



A. Gepp. 



Watson, W., A Somerset Heath and its brj^ophytic 

 Zonation, (The New Phytologist. XIV. p. 80-93. 7 figs. 

 London, 1915.) 



The author gives an account of a wet heath association on 

 Chard Common, in which the dominant vascular plants are Molinia 

 caerulea, Erica tetralix and Myrica gale. He provides plans and dia- 

 grams of the zones. Tracing the zonation of the Vegetation from the 

 wetter up to the drier zones, he finds subdivisicn to be necessary to 

 denote the occurrence of the bryophytes; and he can distinguish 

 seven zones, six of which are characterised by the presence of a 

 particular species. 1. Zone of Potamogetoti polygonifoliiis. 2. Three 

 sub-zones: A. Aneura pinguis and Pellia epiphylla; B. Hypnum 

 scorpioides ; C. Sphagnum cymbifolüim. 3. Aneura multifida. 4. Two 

 sub zones: A. Sphagnum sub}iitens; B. Hypnum intermedium. 5. 

 Hypnum cuspidatian. 6. Brachytheciuni purum. 7. Hypnum cupressi- 

 forme var. ericetorum. The respective associates found in these 

 successive zones are detailed; and the formation and probable history 

 of the Heath is discussed. A. Gepp. 



Anonymus, Decades Kewenses. (Kew Bull. Mise. Inform. N^. 7. 

 p. 344-350. 1915.) 



Polygala palustris, Lace (Burma), Iriumjetta henguetensis, Sprague 

 ''Philippine Islands), Acronychia Barben, Gamble (S. India), Aglaia 



