Manual of California Lichens. 231 



fortunate that a general plan was not adhered to for the genera 

 and fan:ilies. 



We find the usual statement of lichenists that the paraphyses 

 are unifonnly unbranched in a large nuraber of genera. The 

 student is not likely to notice branched paraphyses in manv of 

 these genera without taking great pains, but the writer finds, in 

 a large proportion of these lichens, occasional paraphyses that 

 branch near the apex or nearer the base. 



Naming new species should be left largely to persons of long 

 experience and great knowledge, or to those that have made 

 special studies of certain groups. But Dr. Herre has kept the 

 whole number of new species below a dozen in a work dealing 

 with a region having a peculiar lichen flora and deserves credit 

 for holding back unknown m.aterial rather than publish a larger 

 num,ber of new species. 



The author has avoided the faulty custom of giving an ex- 

 tended and valueless synonymy, copied from earlier works, and 

 has simply cited the original nam.e, the combination used and a 

 few works and herbarium specimens that the student will find 

 helpful in study. Nor has Dr. Herre seen fit to give anything 

 regarding spermagones and spermatia in the descriptions. In 

 this he is in accord with most American workers and has departed 

 from the custom of certain European lichenists. It does not 

 seem that these organs are of sufficient diagnostic value to war- 

 rant their incorporation, especially since the student will seldom 

 see them. 



The treatment of lichen genera is still a problem. Were one 

 in possession of the knowledge necessary for a revision and at the 

 same time disposed to follow rules of priority, he would find it 

 necessary to make a surprising number of changes and transfers 

 in names of genera. The treatment given by Dr. Zahlbruckner 

 in Engler and Prantl, though by no means final, is the best general 

 arrangement of lichen genera that has appeared, and Dr. Herre 

 has done well in following this excellent work. 



A feature of the manual that has not previously found its 

 way into an extended work on Am.erican lichens is the general 

 inclusion of chemical tests in the descriptions. Most American 

 workers have been skeptical about the value of the chemical 

 reactions, but the accumulated evidence culminating in the great 



