ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 633 



Lichens. 



(By A. Lorrain Smith, F.L.S.) 



French Lichens.* — J. Harmand has issued the third part of his 

 systematic and descriptive catalogue of French lichens, which includes 

 the Cladoniae and filamentous genera, such as Usnea, Alectoria, Ramalina, 

 Roccella, Anaptychia, etc. Harmand does not follow the new classifica- 

 tion, which places Cladonia near to Lecidea, and Roccella among the 

 Graphidege ; he follows the older method of classification, according to 

 the form of the thallus. Distribution of the species in French territory 

 is given, and keys are supplied for each genus. 



Lichens from the Island of Samoa.f — The collection was made by 

 K. Rechinger, and the species determined by A. Zahlbruckner. It has 

 been found that the lichen flora resembles that of New Caledonia. 

 There are many forms with Ghroolepus gonidia, especially on twigs and 

 branches in mangrove swamps. Crustaceous forms were generally 

 plentiful, but there were few representatives of Pertusaria, Parmelia, and 

 Usnea. There were only two species of Cladonia, and none of Stereo- 

 caulon. A few new species are described, and one new genus, Pseudo- 

 lecanactis. 



Lichen Notes. V.J— These notes by G. K. Merrill deal with the 

 genus Ramalina. He compares Tuckerman's with Nylander's arrange- 

 ment, and proceeds to give a short review of the different species^ He 

 finds a leading mark of differentiation in the spores, which in R. 

 fastigiata and R. fraxinea are curved, while in R. calicaris and R. 

 farinacea they are straight. The forms of R. calicaris are so many and so 

 varied that a constant character such as the form of the spores is of great 

 importance. 



Lichens Chemically Considered.§ — W. Zopf has devoted much 

 attention to the chemical constituents of lichens, and he here sums up the 

 results of his researches. He reckons some 143 different substances, 

 most of them of an acid character, and all of them crystallisable. He 

 describes his methods of obtaining the acids from the plants ; none of 

 them have been found in any other plant or animal. He gives a list of 

 the reagents that may be employed in determining the presence of the 

 acids, which are also useful from a systematic point of view, though the 

 surroundings, humidity, etc., may influence the quantity and quality of 

 the acid. He does not consider them in the light of protective sub- 

 stances for the lichens, as in many cases they are eaten by animals even 

 when they contain very bitter substances. Zopf also discusses the 

 economic properties and uses of the acids, and finally divides them into 

 their chemical groups. 



* Lichens de France. Paris : Paul Klincksieck, part ii. (1907) pp. 211-478 

 (3 pis.). 



t Math.-Nat. Kl. k. Akal Wiss. YVien, lxxxi. (1907) 66 pp. (1 pi.). See also 

 Hedwigia, xlvii. (1908) Beibl., pp. 172-3. 



X Bryologist, xi. (1908) pp. 48-53. 



§ Jena : G. Fischer (1907) xi. and 49 pp. (71 figs.). See also Bot. Centralbl., 

 cvii. (1908) pp. 196-201. 



