402 Meyen's Report for 1839 on Physiological Botany. 



tunics were derived from the single members into which the 

 primitive tubular cell may by transverse division be dissolved, 

 or whether, as appeared in some cases, the primitive spores 

 with their coverings make their appearance within the tubu- 

 lar cell, whose sides are then absorbed. The drawings ac- 

 companying the article will make this clearer. Sometimes 

 only a part of the tube is changed into primitive spores, etc., 

 and the rest remains undeveloped in one of the primitive cells 

 of its own tube, by which the appearance of stalks sometimes 

 seen on the single primitive cells is explained : as the primi- 

 tive cell is absorbed, they also disappear. In several fruits of 

 Aneura pinguis I was able to observe, at the time when 

 the division of the primitive spore by the contraction of the 

 sides takes place, the existence of a second formation-tunic 

 (it was not the inner surface of the outer one), but neither of 

 them took any part in the division of the spore, as is seen in 

 the delineations. However, last winter I observed that they 

 did take part in the division of the spores in individuals of 

 Aneura pinguis (the large turf variety), inasmuch as the gela- 

 tinous membrane entered into the contractions of the mem- 

 branes of the primitive spores, but was never completely 

 separated, as is the case with Pellia epiphylla. Whether in 

 Aneura the formation of nuclei precedes the division of the 

 primitive spore into four others cannot be observed, inas- 

 much as these cells are filled with a green matter which pre- 

 vents our seeing the internal process : I have also not been 

 able to observe it in Pellia epiphylla, Sphagnum palustre, etc. 

 Directly after the production of the spore by division, each 

 one exhibited a peculiar formation-tunic, just the same as 

 the pollen-grains ; at a later period both the common forma- 

 tion-coverings, as also the special ones, are absorbed, and 

 then the spores lie singly between the tubular cells, which at 

 this time change into elaters *. 



In the past year M. Klotzsch has described a series of 

 Fungi, and accompanied his descriptions -uith excellent de- 

 lineationsf ; in this work (to plate 473) we have a division of 

 the Hymenomycet(B according to the new observations on the 

 structure of the hymenium. The Hymenomycetce may be 

 divided into two groups : Exospora, with free stalked spores, 

 and Entospone, with enclosed unstalked spores. The first 

 division is resolved into the Tetrasporidei, where the straight 



* The plant used for the above observations was the so-called Triclio- 

 stylium arenarium ; but I have convinced myself that Corda's genus Tricho- 

 styUum is the same as Aneura, for the small column which occurs in 7Vi- 

 chostylium also belongs to Aneura. 



t Aeb. Dietrichs Florades Kijnigreichs Preussen, vii., Berlin, 1^39, tab, 

 457-47G. 



