STRUCTURE OF THE O] U.-I'LATES OF AGARICS. 31 



but two generations, each of four spores, that would show another 

 affinity with the thecae of the Ascomycetes, which produce, as is 

 known, for the most part eight spores. There is between the theca 

 and the basidinm such an analogue as to the terminal situation of 

 the vegetable axis and to the production of liquid, granulous, oily 

 contents, that we cannot but compare them completely, despite the 

 differences in size and even of form, with products which are called 

 upon to fulfil the same physiological function. 



American Ferns. In the " Bulletin of the Torrey Botanical 

 Club," for March, 1873, Mr. D. C. Eaton describes two new 

 species of the Transatlantic ferns : — Aaplenium Bradleyi and No- 

 tholcena Newberryi (Eaton). The former of these plants has been 

 found in Massachusetts and in Tennessee, by Prof. P. H. Bradley. 

 In some of its more compound forms it is related to A. montanum, 

 from which it differs in its larger size, more membranaceous texture, 

 narrower outline of the fronds, and shorter stalked pinnae. Some 

 of the denser specimens also resemble somewhat A. lanceolatum of 

 Europe. Notholcena Newberryi has been known to Mr. Eaton for 

 some years, but has hitherto been considered either as Cheilanth.es 

 tomentosa or a white form of Ch. Eatoni. There is, however, no 

 trace of an involucre, even in fruiting specimens, otherwise it bears 

 a considerable resemblance to the ferns just referred to, but is 

 whiter and much more tomentose. In Notholama it comes nearest 

 N. mollis, Kze, from South America, but is much more delicate, 

 and differs in many other important respects. 



Freshwater Algjc. — The April number of the " Quarterly 

 Journal of Microscopical Science" contains a very interesting paper 

 by Mr. W. Archer, in the form of a translation in abstract of Dr. 

 Veit Brecher Wittrock's memoir of the "Freshwater Algae of 

 Gotland and Oland :" two islands in the Baltic Sea. The original 

 paper, in Swedish, was communicated in 1872 to the Royal 

 Academy of Stockholm, and contained an enumeration of some 

 190 species, accompanied by four plates illustrating the Bubject. 



Fries' Epicrisis. — It is said that Prof. E. Fries has in prepar- 

 ation a new edition of his "Epicrisis Systematis Mycologici." 

 The first edition of this work was printed at Upsala in 1836-38 ; 

 since which time numerous and important additions have been 

 made to the species, included under the Hymenomycetes, in this, as 

 well as in other countries. The announcement of a new edition 

 would therefore be welcomed by mycologists in all parts of the 

 world. 



