BOTANY 47 



surface of leaves increases in conductivity, and that the higher 

 percentage of contained salts thus indicated is capable of 

 exerting a favourable influence on the germination capacity 

 of the spores of Botrytis. 



The formation of dendroid appendages on the thallus of a 

 lichen as a response to infection by a species oiNostoc is described 

 by Moreau {Ann. d. Sci. Nat.) in an extensive paper on the 

 anatomy of the thallus of Stictaceous lichens. The develop- 

 ment of these structures is accompanied by the death of the 

 causal alga and results in a profound modification of the 

 thallus as a whole. The facts are all the more striking in view 

 of the presence of Nostocs as the normal algal constituent 

 of the thallus of some members of the group. 



Taxonomy. — In the current number of the Linnean Journal, 

 Compton describes three new species of Coniferae from New 

 Caledonia, the most interesting of which is placed in a new 

 genus Austrotaxus. In the female cone this closely resembles 

 the yew, but the male fructifications differ from those of the 

 other Taxeae in their spike-like form. This tree, A. spicata, 

 which is the southernmost representative of the group, is a large 

 one, 15-25 metres high, occurring in forest between 1,000 and 

 3,000 ft. The wood consists of pitted tracheids devoid of spiral 

 thickenings. A second monotypic genus closely allied to 

 Calliiris is created under the name Callitropsis. C. arancarioides 

 is a monoecious tree some 10 metres high with stiff imbricate 

 leaves in alternating whorls of four members. The female 

 cone bears eight ovuliferous scales and about eight ovules, 

 whilst the embryo is dicotyledonous. 



New Pteridophyta from the same region include single 

 species belonging to Cyathea, Lindsaya, Asplenium, Elapho- 

 glossum, and Gleichenia and one Lycopodium. 



In the December number of the Ann. d. Sci. Nat., Hickel and 

 Camus give an account of the Indo-Chinese species of Quercus 

 and Pasania. Of the former, five species are cited belonging 

 to the section Eiiquercus and eighteen to the section Cyclo- 

 balanopsis. Of these latter, nine are new species. Of the genus 

 Pasania, forty-seven species are enumerated of which no less 

 than twenty-seven are described as new. 



The Euphorbias of Africa are the subject of a monograph by 

 M. Denis, of which the first part appears in the January num- 

 ber of the Revue Gen. de Botanique. Three new species are 

 added. 



Brief diagnoses with some figures of ten new species 

 of peltate-leaved Peperomias are furnished by Trelease in the 

 March number of the Bot. Gaz. 



Hybrids of Orchis purpurella form the subject of a paper by 

 T. and T. A. Stephenson in the Journal of Botany for February. 



