ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 681 



Rhizoctonia.* — Hen- E. Eidam and Herr E. Rostrup j" liave studied 

 the mode of parasitism on the beet of the destructive fungus Rhizoctonia 

 Betse. On the roots of the clover, carrot, and beech are frequently found 

 little balls, at first red, afterwards blackish, which become transformed 

 in the spring into pycuids. Kostrup suggests that Wdzodonia is in fact 

 the mycele of fungi belonging to the Ascomycetes. 



Parasitic Fungus on the lombardy Poplar.^ — M. P. Vuillemin 

 describes a destructive disease of the Lombardy poplar as being caused 

 by the attacl^s of Did ijmosplideria pojnilina, which iu the summer assivmes 

 its pycuidial form of Phomn. 



M. E. Prillieux § confinns this observation, and further identifies 

 the parasite with one "uhich attacks the leaves of the aspen in the 

 conidial state, and which is then known as Fusicladium or Napidadium 

 Tremulse. This fructifies in the summer as a Phoma, iu the winter as a 

 Didymosjihsei-ia. 



Entophytes in Myriopods.|l — Prof. E. G. Balbiani describes three 

 new species of entophytes found in the alimentary canal of the myriopod 

 Cri/ptops. One of these, which aj)pears to have been observed by Plateau, 

 he calls Omphalocyfitis Plateaid. It occurs in the oesophagus of Crijptops 

 pvnctdtus and C. hortensis ; moniliform filaments are attached by a basilar 

 cell to the cuticle ; and the parasite grows by budding from the said 

 basilar cell by acrogenous or intercalary growth in the filaments, aud 

 by lateral budding on the same. Balbiani regards it as a special type 

 of fungi. The second form, also from the oesophagus, he names Mono- 

 nema monilifurme ; it has simple moniliform filaments, without a basilar 

 cell, without ramification, and is less frequent than the former species. 

 A third form, Bhabdomijces Lobjoyi, was also found in the oesoj^hagus, but 

 only in CriipAops liortensis. It consists of isolated cylindrical rods, and 

 is referable to the Blastumycetes. The conids are nucleated, multiply by 

 gemmation, and occiir in the walls of the cesoijhagus, without spreading 

 to other parts of the body. The author also observed in the same hosts 

 what he believes to be a new Gregarine, perhaps the Dadylophonis noted 

 by Schneider, and he noticed, furthermore, a Coccidian in the mid-gut. 



Heliotropism of Phycomyces.lF — M. J. Massart has establishsd a 

 curious fact in connection with Phycomyces nitens. He found that this 

 fungus, when submitted to the opposite actions of illuminations of the 

 same nature, but of unequal intensity, always bent tcjwards the stronger, 

 thus verifying the psycho-physical law of Weber for heliotropism. 



Puccinia vexans.** — Herr P. Dietel records the existence in this 

 species of two kinds of telcutospore and two kinds of uredospore. The 

 teleutospores are either unicellular or bicellular. In addition to the 

 ordinary uredospores, there are others which resemble teleutospores, not 

 only in their appearance, but also in the fact that they will ajjparently 

 germinate only after hibernating; the author proposes for these the 

 term mesospore. 



* JaLrb. Schles. Vaterl. Cultur, 1888. See Bonnier's Eev. Gen. de Bot., i. 

 (1889) p. 156. 



t Overs. K. Dansk. Vidensk. Forliandl., 1888. See Op. cit., p. 15G. 

 X Comptes Eendus, cviii. (1889) pp. 632-5. § T. c., pp. 1133-5. 



II Journ. Anat. et Physiol. (Robin), xxv. (1889) pp. .5-45 (2 pis.). 

 1 Bull. Acad. Eoy. Sci. Belgique, xvi. (1888) pp. 550-2. 

 ** Hedwigia, xxviii. (1889) pp. 177-9. 

 1889. 3 i; 



