ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 579 



ripe antberidium ; and (2) tbe thin-walled and large-celled water- 

 absorbing tissue composing tbe cusbion on tbe tballus, in chambers of 

 which the antheridia develop. The expansions of the tissue aud the 

 mucilage as they absorb water tend respectively to decrease and increase 

 the size of the antberidial chambers. As tbe chambers are open above 

 the distending and compressing strains result in the rupturo of the 

 antberidium and the discbarge of its contents through tbe mouth of the 

 chamber. 



Red-coloured Hepatics.* — A. Casares Gil records a few observations 

 as to the reddish coloratiou of certain hepatics. He inclines to tbe 

 opinion that its purpose is not to absorb a greater amount of light or 

 heat but to act as a shield to regulate the intensity of the more re- 

 frangible rays that penetrate tbe plant. Some frondose hepatics such 

 as Targionia hypophylla and Grimaldia didiotoma are deeply coloured 

 on the under surface and grow in dry sunny spots. In the early morning 

 they remain expanded while tbe dew is on them, and then fold in their 

 coloured margins so as to cover and protect the green upper surface. 

 In Beboulia hemisphserica the distribution and depth of the red colour 

 of the lower surface is projjortional to the intensity of light which the 

 plant has to live in. Tbe red antheridia of some genera and the reddisb- 

 violet root-hairs of others have yet to be explained. 



Genus Thamnium.f — N. C. Kindberg begins a monograph of tbe 

 genus Thamnium, as emended by himself, importing into it tbe whole 

 of Porotrichum and a large number of species from various other genera. 

 In all, he includes 96 species and treats of 20 in the present contribu- 

 tion. Many so-called species he reduces to mere synonyms. In the 

 introduction he supplies lists of characteristics which he finds to be, or 

 not to be, trustworthy for discriminating the species. He also adds a 

 bibliography. He divides tbe genus into Eu-Thamnium, Porotrichum, 

 Camptolepns, and Lembophyllum ; and subdivides the first three of these 

 sections into Leiophylla and TrachyphyUa ; and by further manipula- 

 tions he reduces the ultimate groups of species to conveniently small 

 dimensions. 



French Muscinese.— E. Levier J describes Biccia Crozalsii, a new 

 species belonging to the ciliate section of tbe genus ; and shows how it 

 may be readily distinguished from its allies. It was found in tbe south 

 of France near Montpellier, by A. Crozals, who has also discovered 

 fertile plants of three other species,— B. macrocarpa Levier, B. papillosa 

 Moris, and B. Gougetiana Mont.— which are additions to the French 

 flora. 



G. Dismier § publishes a note on some mosses and hepatics new to 

 the French Ardennes, or at least rare, whicli be gathered during a trip 

 in that district last Whitsuntide. To his surprise he found the exclu- 

 sively calcicolous moss Eucladium verticillatum growing on a slaty 

 rock, and supposes it to have derived sufficient carbonate of lime for its 

 -existence from the water percolating down from some houses situated 

 overhead. 



* Bolet. Soc. Espafl. Hist. Nat , ii. (1902) pp. 2 17-220. 

 t Hedwigia, xli. (1902) pp. 203-24. 

 t Rev. Bryolog, xxix. (1902) pp. 73-6 (figs, in text). 

 § Tom. cit.. pp. 89-90. 



