ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 235 



Brown considers that there is no evidence of any fusion of nuclei in 

 the ascogonium. The nuclei of the ascogenous hyphae probably arise 

 from a single nucleus with the haploid number of chromosomes, and their 

 relationship to each other is therefore of no significance. The vegetative 

 hyphas form large storage cells in the hymenium ; the nuclei in these 

 cells frequently fuse to form a single large nucleus. 



The development of the ascocarp indicates that all of its structures 

 are homologous with those of the Pezizinete, and that Leotia is closely 

 related to that group. 



Uredinese. — P. and H. Sydow* have issued the section of their 

 monograph dealing with the genus Uromyces. They give a short 

 historical sketch of Uromyces, and a general description of its occurrence 

 and development. It is like Puccinia except in the teleutospore stage, 

 the spores being only one-celled and possessing one apical germinating 

 pore. Many of the species live on one host, others alternate on different 

 hosts. The authors include in Uromyces the genera Trachyspora and 

 Piholaria, and they reject the numerous genera established by Arthur, 

 based as they often are on our as yet imperfect knowledge of the 

 different life stages of the species. 



Laszlo Hollos f publishes a list of 171 species of Uredineas from 

 Hungary, some of them very rare forms, and most of them new for that 



region. 



F. Zach | describes researches he has made on the relation between 

 host and parasite in the Uredineae. He demonstrated phagocytose 

 bodies in the cells invaded by the parasite both in root and leaf. These 

 bodies are larger or smaller, the latter are Eriksson's Plasmanukleolen. 

 In many cases there seems to be a symbiotic relationship between host 

 and parasite, the host being uninjured by the presence of the fungus. 

 Finally, he concludes that new outbreaks of rust are due to spore- 

 infection. 



F. C. Arthur § describes a number of new species of Uredineas from 

 various regions of the United States. They belong to the genera 

 Puccinia, Uromyces, Uropyxis, Uredo, Peridermium, and JEcidium. 

 Many of them were collected in the preparation of the North American 

 flora. 



Y. Orishimo || has established a genetic connexion between Col&o- 

 sporium on Aster scaler and Peridermium Pini-densiflorse by means of 

 infection experiments ; both forms are now included under Goleosporium 

 Pini-Asteris. The author gives a list of Coleosporium species in Japan. 



Study of Smut-infection. ^[ — Fr. Honcamp and H. Zimmermann 

 have tested smut spores that had passed through the bodies of various 

 animals. It has been generally held that feeding animals with smutted 



* Monographia Uredinarurn, II. 2 (Leipzig, 1910) xix. and 396 pp. (9 pis.). 



t Magyar Bot. Kozlem., ix. 2 (Budapest, 1910) pp. 161-9. See also Hedwigia, 

 1. (1910) Beibl., p. 164. 



t SB. k. Akad. Wiss. Wien, Math.-Nat. Kl., cxix. (1910) pp. 307-30. See also 

 Bot. Centralbl., cxvi. (1911) pp. 17-18. 



§ Bull. Torrey Bot. Club, xxxvii. (1910) pp. 569-80. 



|| Bot. Mag. Tokyo, xxiv. (1910) pp. 1-5. See also Bot. Centralbl., cxvi. (1911), 

 pp. 94-5. Tf Centralbl. Bakt., xxviii. (1910) pp. 590-607. 



