466 Meyen's lleport for 1839 on Physiological Botany. 



distinguishes this genus from Uredo, so that they cannot both 

 be comprehended under the name of Cceoma. M. Leveille re- 

 marks, that Fries has rightly observed the difference between 

 Uredo and ^cidium. 



M. Leveille says the granules of Uredo are generally consi- 

 dered as spores, but obsenations to prove this are very rare : 

 M. Prevost was the first who saw that a byssus-like tissue 

 was produced from spores of Uredo caries, De C, when ex- 

 posed to moisture, and M. DeCandolle has made the same 

 observation. [Even if the production of germinal filaments 

 from the vesicles of the bunt [SchmierbrandJ has really been 

 observed, Avhich I have as yet not succeeded in doing, still 

 my own observations on the production of the bunt in Mays 

 (see Report, 1838, p. 162.) show that it is a diseased forma- 

 tion in the interior of the cells, and may be regarded as a true 

 Entophyte,^ M. Leveille also mentions the production of the 

 bunt in Mays, and says that it is also produced by ramified 

 filaments which are short and jointed, and from these the 

 brown spores separate themselves, &c. [Did M. Leveille 

 mention these observations in 1837 ?] 



Finally, there is a division of the Uredines into three smaller 

 families : 1. jEcidinece, with the genera Rceste/la, Reb. ; ^ci- 

 dium, Pers. ; Peridermium, Link, and Endophylhmi, Lev. 

 2. Uredinea \\\i\i Phragmidium, Ijink ; Puccinia, Pers.; Uredo, 

 Pers.; Podisoma, Link, &c. 3. Ustil ayinece vi'iih Ustilayo, 

 Link; Sporisorium, Ehr., &c. 



Mr. W. Valentine* has laid before the Linnaean Society his 

 observations on the structure and development of the organs 

 of reproduction of Pilularia globuUfera : they contain much 

 interesting matter, and it is to be hoped the treatise will soon 

 be pubHshed with delineations. 



M. Alexander Braunf laid before the Meeting at Frei- 

 berg his observations on the germination of the spores of 

 Marsilea quadrifolia. The fruit of Marsilea he considers as 

 a part of the leaf on the stalk of which it is seated. The nerva- 

 tion [Berippung] of this fruit-leaf is pinnate, and on the side- 

 ribs are formed the placentae which bear the sporangia, which 

 are of two kinds, and each sorus is covered with a closed in- 

 dusium, &c. According to this view, the formation of fruit 

 in Marsilea is similar to that of the Ferns, and these, as well 

 as the Equisetecs and Lycopodia, would then bear their spo- 

 rangia on the leaves, herein differing from the Mosses. 



• Annals of Nat. Hist, June 1839, p. 260. Linn. Trans., vol. xviii. p. 483. 

 t Flora von 1839, p. 297. 



