1915] CURRENT LITERATURE 77 
cytosis is an important feature that should be looked into. As to lichens, it 
is noted that the chemistry of the plant complex is very different from the 
chemistry of the sum of the components, grown as separate individuals; the 
nutritive relations of the algal symbionts are not known. Similar suggestions 
are made relative to the need of investigating the chemistry of esa prctis as 
illustrated by ergot, wheat rust, and their host plants.—H. C. Cowzes. 
Lichens in relation to their substratum.—BACHMANN,®” who for many 
years has paid attention to the substratum relations of lichens, has reported 
his observations on the lichens of granite and quartz. Granite is decomposed 
into a claylike substance by lichen tissue with some rapidity, the micaceous 
constituents being particularly subject to ready decay. The quartz elements, 
on the other hand, are extremely resistant to such decomposition. 
In a later paper BACHMANN reports the results of studies on calcareous 
lichens with Chroolepus gonidia. He finds that the Chroolepus itself is able 
to dissolve calcium carbonate, so that after a time a limestone becomes per- 
forated in spongelike fashion through the agency of the Chroolepus cells of the 
fungal hyphae. As soon as the Chroolepus cells become inclosed by hyphae, 
they bud in a yeastlike manner and take on bizarre forms. On account of its 
position within a rock, such a — retains moisture longer than do ordinary 
superficial lichens—H. C. Cow tes. 
Taxonomic notes.—WERNHAM“ has described a new genus sales oie 
of Wie from Colombia. It belongs to the tribe Mussaen: 
4 has described two new species of We ee one tie New 
Caledonia cd the other from the mountains of Ngoy 
BENEDICT® has begun a revision of the genus Vittaria. The first paper is a 
discussion of seven species, representing the subgenus Radiovittaria, and 
includes two new species. 
Baker‘ has published a study of the African species of Crotalaria, preced- 
ing the descriptive list by a historical introduction, and also a discussion of the 
delimitation of the genus. The paper recognizes 309 species, the genus 
extending from Egypt and the Soudan and the Sahara to Cape Colony in the 
* BACHMANN, E., Die Beziehungen der Kieselflechten zu ihrer Unterlage. II. 
pares und Die ee: Deutsch. Bot. Gesells. 29:261-273. figs. 4. 1911. 
———, Der Thallus der singgieaerga = Flechten mit Chroolepugonidien. 
Ber, ess Bot. Gesells. 31: 3-12. pl. 
RNHAM, H. F., New HOES a ‘eats America. Jour. Botany 52: 
225-277. pl. 533. 1914 
* Diuer, R. A , Three Conifers. Jour. Botany 52: aoe: 1QT4. 
# Benenict, R. Cc, A revision of the genus Vittaria S E. Smith. Bull. Torr. 
ot. Club Ng aed tas. 7. pls. 15-20. 1914. 
B » E. G., The African species of Crotalaria. Linn. Soc. London. Bot. 
49° 241-425. gre pie 1914 
