ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 345 



may be derived from forms possessing pollinodiuni and ascogonium, yet 

 in place of fusion between the nuclei of these two organs there is now 

 fusion between two ascogonial nuclei. This fusion takes place in 

 Monascus in the ascogonium ; in Py rone-ma confiuens and some species 

 of Ascobolus it takes place in hyphae which arise from the ascogonium. 

 In most of the Ascomycetes the distinction between pollinodiuni and 

 •ascogonium is partly or entirely lost, and nuclear fusion takes place in 

 the ends of the ascogenous hyphas. 



White Mildew of Euonymus.* — Euonymus japonica is one of the 



commonest evergreens of Italian gardens. V. Peglion describes the 

 attack of the mildew Oidium, which destroys the leaves. As the sys- 

 tematic position of this conidial form is somewhat doubtful, the author 

 names it 0. Euonymi-japonicm. He found a species of Cicinnobolus 

 parasitic on the mould. The fungus winters in the tissues of the 

 Euonymus, and grows in spring with the new vegetation. 



Erysiphacese.f — E. S. Salmon records results obtained in his cultural 

 •experiments with Erysiphe on Euonymus japonicus. The same plant has 

 been frequently infested by a similar parasite in Japan, and it seems 

 probable that the fungus has been introduced here from that country, 

 though in the absence of perithecia it has been found impossible to 

 identify it with absolute certainty. It has been proved 'by experiment 

 not to be identical with the Erysiphe on Euonymus europceus. The 

 leaves of E. radicans and some of its varieties, were the only other 

 ■species of host plants that were susceptible to the fungus. All other 

 species inoculated proved to be immune. 



In another paper,J the author adds Erysiphe taurica, conidial stage, 

 to the number of Erysiphaceas that have been found to be parasites or 

 hemiparasites. The mycelium of the fungus is endophytic ; it branches 

 freely in the intercellular spaces of the host tissue, and may invest the 

 mesophyll cells closely. The conidiophores pass out through the stomata, 

 and bear the chains of conidia on the surface of the leaf. 



Aspergillus.§ — 0. Wehrner has studied this genus in its morpho- 

 logical, physiological, and systematic aspects. He finds 20 species in 

 Germany and Switzerland, which he classifies in three groups, according 

 to the colour of the young conidia — green, dark brown, or yellow. There 

 •are also two white species — A. candidus and A. alb us. 



North American Ustilagineae.|| — G. P. Clinton has written a mono- 

 graph of the fungi of this natural order that occur in North America. 

 Of the 24 genera recorded, 19 have been found in America, and are 

 described by the author. He describes nine new species, and gives a 

 key to genera and species. 



* Atti Eeale Accad. Lincei, cccii. (1905) pp. 232-4. 



+ Ann. Mycol., iii. (1905) pp. 1-15(1 pi.). J Tom. cit., pp. 82-3. 



§ Mem. Soc. Phys. Hist Nat. Geneve, xxxiii. No. 4 (1904) 157 pp. (5 pis.). See 

 also Ann. Mycol. iii. (1905) pp. 117-18. 



11 Proc. Boston Soc. Nat. Hist., xxxi., No. 9 (1904) pp. 329-529. See alt«o 

 Hedwieria, xlvi. (1905) p. 61. 



