1898] CURRENT LITERATURE 285 
be ia the main ‘a condensed retrospect of Krempelhuber’s Geschichte der 
Lihenologie,” Krempelhuber’s book bearing the date of March 1886. Dr. 
Scineider adds two periods to bring the history up to date: one from 
Schwendener (1886) to Reinke (1894), the other from Reinke (1894) to the 
of 1896. Dr. Schneider admits that Reinke’s propositions have not 
generally been accepted as correct, but maintains that they “are based upon 
‘ound argument and should, therefore, mark the beginning of the period in 
— lichens are recognized as a distinct class of plants ; such recognition 
Heng based upon physiological considerations.” 
oleae chapter is devoted to symbiosis. The subject is divided 
“er a : myobiosis (parasitism), nutricism, and mutualistic symbiosis. 
Resicd i Saga and individualism are distinguished, the forther 
tach other for Ng sola that the symbionts are not wholly dependent upon 
Ymbionts is absol erm naga ise sana — ee pints 
phenomenon of 35 ed dependent upon the symbiotic association. The 
Be Stisies 51 ivi ES is typically met with in lichens, according to 
be considered'a . ly forms the basis for Reinke’s claim that they should 
mn ofthe thallus class of plants. Then follows an interesting discus- 
tit parts, their as apothecium, the structure and function of their differ- 
In the consider. 2 of growth, mechanical adaptations, etc. 
Schneider ica. 3. of the reproduction and propagation of lichens, Dr. 
Y only an insi ifi sag eee are unreliable aids to reproduction, and 
Pore upon ha a part in the maintenance of species, because the 
"cause in some s ation may not find the proper symbiont alga and also 
this view of the a the spores are only rarely developed. It is doubtful 
ie : vert will find full acceptance. 
families of Sings a ote devoted to the polyphylogeny of lichens. Deby 
h the “lit Allg as probable ancestral groups of fungal symbionts, 
types at prese ag made that it is impossible to study out the ancestral 
Ris erent oe N ine genera of alge are given which are known 
The system 7 5 Ic relationship to form lichens. 
by the (cn my di . Dr. Schneider» 
ial system” .. that “there is at present no satisfactory natural or 
Sera, and Steck then proposes an arrangement into orders, families, 
te Hchens ann 
or b 
o wing fro road that all the varietal forms may be easily accommodat 
COrrect one 
es — orders recognized are the Ascolichenes, Basidiol 
ms family €s, based on the method of spore formation. 
Characters the 
: probable fungal ancestors, the 
