ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 627 



Development of the JScidium.* — A. F. Pavolini is engaged in the 

 study of the JEcidium of Uromyces Dactylidis and publishes a preliminary 

 note on the results of his work. He gives a sketch of the work done 

 and of the views held on the question of sexuality in the JEcidium by 

 Massee. Neumann, Sappin-Trouffy, Blackman and Christman. Pavolini 

 selected this species of Uromyces as not only Massee and Neumann, but 

 Blackman and Fraser in their last paper deal with this form. He col- 

 lected specimens of different ages on the leaves of Ranunculus Ficaria. 

 In the youngest stages of the JEcidium he noted an irregular mass of uni- 

 nucleate hyphas, the lower more compact and with more dense proto- 

 plasmic contents than the upper. At a later stage the hyphae are arranged 

 in parallel or slightly oblique lines, the upper cells of which are already 

 binucleate. The nuclei lie side by side or superposed, the difference in 

 position being caused by the position of the cell from which the second 

 nucleus has migrated ; occasionally the parallel hypbre are bifurcate. 

 The binucleate cells after repeated division form the mother-cells of the 

 fficidiospores. The author, therefore, sees here a case of reduced fecunda- 

 tion with equal gametes. He saw no instance of division in uninucleate 

 hypha3, the double condition being always due to migration. Cells were 

 seen with three or four nuclei, but the reason of that may possibly be 

 pathological, or due perhaps to the disappearance of the membrane 

 between two cells. He is not sure yet if " migration " be the proper 

 term to use in the uniting of the nuclei. A superficial layer of sterile 

 cells was not seen, all the cells seemed to be normally nucleate and 

 equally functional. The two conjugate nuclei remain distinct until the 

 development of the teleutospore, when fusion takes place. 



Uredinese.t — W. Tranzschel publishes results of his culture experi- 

 ments during 1906 and 1907. He finds that Puccinia Porri is one of the 

 Heniipuccinia?, the sporidia producing only uredospores ; that P. Erio- 

 phori forms aecidia on Senecio paluster and Ligularia sibirica. The 

 JEcidiwn-iorm of Puccinia litoralis was developed on Sonchus arvensis, 

 S. asper, and ;S'. oleraceus ; JEcidium Trollii is connected with Puccinia 

 Dietrichiana on Aryopyrinurn caninum. Other less important results are 

 also chronicled. 



The same author % has written a paper on JEcidium-forma with 

 golden-brown spore-membranes. He gives descriptions of the species 

 with that type of spore ; they were mostly collected in Eastern countries. 



Trabut § reports a, rust on cabbages at Sidi-Aissa, due to JEcidium 

 Brassicse sp. n. The gardens were surrounded by ditches filled with 

 Phragmites isiaca. Trabut thinks the JEcidium may belong to the rust 

 Puccinia isiacse. 



Coloured Drawings of Mushrooms, edible and poisonous.|| — A 

 series of coloured drawings of held and cultivated mushrooms, and 



* Bull. Soc. Bot. Ital. (1910) pp. 83-8. 



f Arb. Bot. Mus. k. Akad. Wiss. St. Petersbourg, vii. (1909) pp. 1-19. See also 

 Ann. Mvcol., viii. (1910) p. 415. 



t Tom. cit., pp. 111-16. See also Ann. Mycol., viii. (1910) p. 415. 



§ Rev. Hort. Algerie, xi. (1907) pp. 285-6. See also Bot. Centralbl., cxiii. (1910) 

 p. 632. 



il Gui^e to Worthington Smith's Drawings of Field and Cultivated Mush- 

 rooms and Poisonous or Worthless Fungi often mistaken for Mushrooms. British 

 Museum (Natural History), 1910, 22 pp. (with text figs, and large coloured plates). 



