228 Lichenes. 



to the North American forms. The following are described as new: 

 Ramalina farinacea forma latus Merrill, R. linearis forma spinulosa 

 Merrill, R. inflata var. soredians Merrill, the first being from San 

 Juan Island, Washington, and the last two from Jamaica, 

 B. W. I. Maxon. 



Malme, G. O. A., Nägra ord om de i Stockholmstrakten före- 

 kommande Parmelia- arterna af Undersläktet Hypogymnia. 

 [Some words about the Parmelia-species of the subgenus 

 Hyp. found in the environs cf Stockholm]. (Svensk botanisk 

 Tidskrift. I. p. 336—341.) 



Referring to the article of Bitter in Hedwigia 1901, the 

 author notes their occurence at Stockholm and he contradicts the 

 supposition of Birg er Nilson, that Parmelia Aubiilosa (Hagen) Bitt. 

 and P. farinacea Bitt. should only be modifications of P. physodes 

 (L.) Ach. Lind (Copenhagen). 



Sernander, R., Om nägra former för art-och varietetsbild- 

 ning hos lafvarna. [On various forms of the origin of 

 species and variejties by the lichens]. (Svensk botanisk Tid- 

 skrift. I. p. 97-115 and 135—186. 1907. With a German resume, 

 5 figures in the text and 5 plates.) 



The author has made a number of important observations con- 

 cerning the morphology, biology and Classification of the lichens, 

 and he treats them in a masterly way, continually taking into con- 

 sideration the mutationtheory of de Vries. 



The article is divided into 4 chapters. 



I. Diagnose of the idea lichenspecies and the gonidiasubstitution 

 as a speciesmaking factor. The systematic place of a liehen solely 

 depends upon the lichenfungus, the relation of the lichenfungus to 

 the lichenalga is pure biological and a Separation of the lichens in 

 different genera only based upon a difference of the inclosed algae 

 {Lecanora Prevostii (Fries) Th. Fr. and. Jonaspis epulotica (Arn.) Th. Fr.; 

 Solorina crocea (L.) and Solorinina crocoides (Nyl.); Pyrenopsis piilvi- 

 nata (Schaer.) and Lecanora granatina (Somf.) is just as rejectable 

 as to separate the lichenfungi with algae from the same fungi 

 without algae [Arthonia and Mycarthonia; Bacidia and Mycobasidia; 

 Calicium and Mycocalicium). 



Of the biology of Lecanora gelida (L.) Ach. is given an extended 

 account with beautifull photos. It is found in 3 different forms, 

 according to its combination with Palmella, Chroococciis or Stigo- 

 nema, all of them living in antagonistic Symbiose; the Palmellalichen, 

 being the quiekest growing, will Surround the Chroococcas- or 5//- 

 gonerna-Mchen (these two were called Cephalodiiun) , but the Cepha- 

 lodium will grow upward and then Stretch out and covering the 

 Palmellalichen partially kill it. 



II. Depigmentations as retrogressiv varieties. A specimen of 

 Rosmarinus officinalis at Montpellier was quite overgrown with 

 Xanthoria parietina (L.) Th. Fr. of which the individuals most 

 exposed to the light had a strong yellow colour and were to classify 

 as var: aureola (Ach.); but those in the shade were glaucous and 

 were to classify as var: livida de Not. Also among Physica and other 

 genera such variations are found, which are only caused by the 

 effect of the light and the amonnt of chrysophanic acid, these are 

 called false colour-varieties. On the contrary Cladonia has genuine 



