ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 485 



T. incnisfans (Halymenia incrustans J. Ag.) and T. Pikeana (Galax- 

 aura Pikeana Dickie); Glaphyrymenia, belonging to the tlbody- 

 meniaceaB, with one species ; and Merrifieldia, also placed under 

 RhodymeniaceaB, with one species, M. ramentacea {Chondria ramen- 

 tacea C. Ag., Hypnea ramentacea J. Ag.). The little-known genus 

 Marchesettia Hauck is placed near Thamnoclonium ; and Melanoseris 

 Zan. is closely allied to PoJlpxfenia. Halymenia saccata Harv. is 

 placed under Bindera, and Amansia marchantioides under Placojohora. 



New Fresh-water Algae.* — Mr. F. Wolle describes a number of 

 fresh-watsr algJB from Florida, including the following new species : — 

 Ecfocarpus rivularis, (Edogonium cataractum, Dtdyosphserium Hitch- 

 cockii, Zygnema purpurea, Mesocarpus crassus, Staurastrum Tokope- 

 kaligense. 



Burmese Desmidieae.f — Mr. W. Joshua describes a collection of 

 DesmidiesB taken from the leaves of Pistia Stratiotes from a pond in 

 the neighbourhood of Rangoon. Thirty - three new species are 

 described. 



Animal character of Diatoms. J — Dr. G. W. Eoyston-Pigott writes, 

 " For my own part, considering their peculiar power of movement and 

 sustentation, and also of conjugation, as well as their unaccountable 

 strength of movement, I do not doubt that diatoms are living animals." 



Lichenes. 



Glceolichenes- § — Herr K. B. J. Forssell contributes a monograph 

 of this group of Lichens, also known as Homolichenes, homoemerous 

 lichens, CoUemacei, Phycolichenes, and gelatinous lichens. Their 

 gonidia are always Phycochromaceae, belonging to Nostocaceae, 

 Eivularieae, Scytonemeae, Stigonemaceae, or Chroococcaceae. Their 

 membranes always deliquesce on moistening to a homogeneous pulp ; 

 the thallus displays no differentiation of cortical, medullary, and 

 gonidial layers. The gonidia are blue-green, surrounded by a thick 

 gelatinous membrane, and alwajs multiply by dichotomous division. 

 The author points oi;t that in the construction of lichens similar fungi 

 may be associated with very different algae, or very similar algae with 

 different fimgi. 



In classifying lichens the author assigns the first importance to 

 the mode of fungal reproduction, next to the nature of the gonidia. 

 On this plan the Glceolichenes must be placed under Ascolichenes. 

 The chroococcaceous gonidia form an " indifferent symbiosis, i. e. the 

 algal cells undergo no change in becoming gonidia, but the gonidia may 

 undergo various modifications. The sole common character of the 

 hyphae is their immersion in the mucilaginous mass formed by the 

 deliquescence of the membrane of the gonidia. They are sometimes 



* Bull. Torrey Bet. Chib, xii. (1885) pp. 125-9 (1 pi.), 

 t Journ. Linn. Soc. Lond. ^Bot.), xxi. (1886) pp. 634-54 (4 pis.). 

 X Engl. Mech., xliii. (188«) p. 115. 



§ Forssell, K. B. J., ' Beitr. zur Kennt. der Anat. u. System, dor Glceo- 

 liclicnen,' 118 pp., Stockholm, 1885. 



