170 NOTES AND MEMORANDA. 



BWoUen, they open by a dehiscence into two lips, and from each 

 escapes from two to three colourless hyaline spores, evidently pro- 

 vided with a membrane. The extremities of these same filaments, 

 which have remained regular, and whoso cells are rectangular, and 

 more or less elongated, terminate by bunches of spores, some rounded 

 and arranged in umbellated rows around the supei'ior cell ; others, 

 elongated into rods which become smaller and smaller in proportion 

 as we ajiproach the extremities, are in ramified bunches. Both 

 resemble Spicaria. 



We ought perhaps to class among the means of reproduction some 

 bodies met with in fewer number than the preceding : they are 

 larger than the spores of the sporangiolos, are reticulated on the 

 surface, and marked with a star, generally with three points ; most 

 often they are found free ; in one case one of them seemed to be 

 carried by a filament, and it seemed embraced at its base by two 

 branches which were curved towards it. 



M. Marchand draws the conclusion that Hygrocrocis arsenicus, 

 formerly placed amongst the Algte, is a fungus belonging to the 

 Dematiei ; a practical confirmation of opinions given a priori by 

 Decaisne, Bornet, Van Tieghem, &c. 



|The "Plastids" of the lower Plants.— M. E. Hallier has published 

 a book on this subject, in which he deals with the parasitic diseases 

 which attack the potato and the cabbage butterfly. The author 

 dwells at length on Peronospora, which in his opinion is not a real 

 parasite, but a saprophyte. He asserts that he has seen Bacteria and 

 Vibriones originate from the plastids of Peronospora. He gives the 

 name of plastids to the accumulations of protoplasm which are formed 

 not only in the conidia, but also in the interior of the mycelium of 

 this cryptogam. In his opinion the contagious character of the 

 disease, and the cause of the alterations, are to be found in the ex- 

 istence of these agents of putrefaction, Bacteria or Vibriones. He 

 has also studied another disease of the potato, which he thinks is due 

 to Pleospora pohjlricha, Tub, although he has not proved by actual 

 exjjeriment that it is actually this Pleospora, a j)arasite on grasses, 

 and moreover rare in Germany, which penetrates into the soil and 

 thence into the tubercules of the potato to cause this disease. A very 

 common Lejiidoptera, Pieris Brassicce, is attacked by two diseases, a 

 kind of mnscardine, and a kind of gattine. The former is contagious, 

 and is apparently reproduced by the conidia arising at the extremity 

 of the filaments which have passed through the body of the insect. 

 The second is caused by one of the Torulacei, and the author thinks 

 that here again the contagion and disorders are not due directly to 

 the joints of Arthrococcus, but to Micrococci developed in the plastids 

 of this Arthrococcus. * 



Staining for Fungi. — Dr. W. Hassloch has obtained excellent 

 results in the examination of fungi by using gold chloride as a stain- 

 ing fluid. He employed a one-half per cent, solution, which stains 



* ' IJull. Soc. Bot. de Fraucu,' vol. xxv. (1878) p. G6. 



