ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 1043 



In two species of Strigula from Cuba and Caracas, Dr. Muller 

 found stylospores of a very peculiar form, with a number of transverse 

 divisions, amounting to even eight, instead of the ordinary bicellular 

 condition, with a power of growing to more than ten times their original 

 length. These facts lead to the hypothesis that spermogonia and 

 sperraatia are possibly connected genetically with pycnidia and 

 stylospores ; that spermatia are, in fact, nothing but young stylo- 

 spores, and spermogonia nothing but young conditions of pycnidia. 



The ordinary view that the spermatia of lichens are male sexual 

 organs which have lost their function, is combated on the following 

 grounds : — The spermatia spring from basidia, and have therefore a 

 totally different origin from antherozoids. They are not naked nucleated 

 masses of protoplasm, but are provided with a cell-wall, like sjiores 

 and ordinary vegetative cells. They are not organs of special nature, 

 but have the structure of an ordinary unicellular spore. There is no 

 organ in lichens w'hich can be regarded as an oogonium. The sexual 

 reproduction observed by Stahl is not essential to lichens, for Fiinf- 

 stiick has shown * that in Peltigera fructification and ascospores are 

 produced without the agency of spermatia ; the swelling of the 

 ascogonium taking place vegetatively without the co-operation of a 

 trichogyne. The author contends that in lichens no true j)rocess of 

 sexual reproduction has been observed, but at the most a doubtful 

 " copulation " in the older sense of the term. 



Dr. Muller supports the older view of the autonomy of lichens, 

 against the newer theory of " symbiosis." He complains of de Bary's 

 recently published 'Anatomic u. Physiologic der Pilze,' that in 

 summing up the arguments in favour of Schwendener's hypothesis, he 

 omits all reference to Minks's and his own work on Microgonidia, 

 and incorrectly uses the terms "conidia" and "gonidia" as convertible. 

 Dr. Muller considers this theory as completely demolished by the 

 discovery of Minks j that the gonidia of lichens exist from the first in 

 the hyphfe or hypha-like organs, in the form of minute very light- 

 green microgonidia, some of which develope, when the hyphal mem- 

 brane becomes converted into mucilage, into gonidia. These facts he 

 claims to have confirmed by independent observation. 



Anatomy and Development of Lecanora granatina.$— Dr. K. B. 

 J. Forssell has carefully studied the structure and dcveloi>ment of 

 this lichen, the peculiarities of which have caused it to be placed by 

 different authorities in several different groups. The criistaceous 

 thallus contains both yellow-green (palmella) and blue-green (glceo- 

 capsa) gonidia, inclosed in a reddisli gelatinous envelope ; and these 

 different parts of tlie tliallus maybe either quite dissociated or closely 

 united together ; the two kinds of gonidium becoming sometimes 

 completely intermingled in the course of development of the lichen. 

 Between the different parts of the thallus are also free gloeocapsa- 

 cfjlonies, and otliers into whicli tlie hyphaj are beginning to i)euetrato. 

 Those parts of the thallus which contain these colonics are especially 



* See tJii.s Journal, ante, p. 400. 



t Heo this Journal, ii. (1870) p. 311. 



i Bot. Centralbl., xxii. (ISH.")) pp. .'J4-8, 85-0. 



