928 SUMMABY or CUERENT EESE ARCHES RELATING TO 



the oogonium, attaches itself firmly to the investing membrane of the 

 oosphere, finally pierces it, and the entire contents of the antheri- 

 dium becomes absorbed by the oosphere, which now becomes invested 

 with a double membrane, and assumes the character of an oospore. 



The systematic position of Bhizomyxa hypogcea is regarded by 

 Borzi as referable to the Ancylistaceas, near to Lagenidium, Mycocytium, 

 and AcMyogeton ; but it also has many points of resemblance to the 

 Chytridiacete, especially to Woronina and Olpidiojpsis. 



Effect of light on the Cell-division of Saccharomyces.* — L. 



Kny has carried on a series of experiments on this subject, as the 

 result of which he comes to the conclusion that cell-division takes 

 place in Saccharomyces cerevisice as actively in moderate light as in 

 darkness. 



Behaviour of Blood-corpuscles to Pathogenous Micro-Organ- 



isms.l — The observations which E. Metschnikoff has made on 

 Daphnim have given results, which, if they are confirmed, seem to be of 

 the greatest importance in the knowledge of parasitic diseases and 

 their treatment. 



The author observed a disease in the Daphnice, produced by the 

 penetration and development of a fungus which eventually kills the 

 host. Inoculation experiments on healthy Daphnice showed that the 

 cells of the fungus were attacked by the blood-corpuscles in the 

 interior of the organisms, and finally overcome. Both spores and 

 gonidia showed changes of form which resulted in their complete 

 destruction. On the other hand, the blood-corpuscles suffered from 

 the parasites, as some of them were seen to burst up into several pieces, 

 whereby the gonidia were freed from the parent-cell. It was further 

 observed that blood-corpuscles in the neighbourhood of fungus cells 

 dissolved and completely disappeared. The number of the blood- 

 corpuscles dissolved increased in proportion to the advance of the 



Metschnikoff concludes from his observations that " the infection 

 and disease of the Daphnice consist in a struggle between two living 

 organisms, the fungi and the blood-corpuscles. The former are lowly 

 organized unicellular plants ; the latter are the lowest tissue -elements, 

 and show the greatest resemblance to the simplest organisms." The 

 issue of this struggle varies at the commencement of the infection by 

 spores, the latter are mostly killed, and the blood-corpuscles obtain 

 the upper hand. But when the disease has already broken out, the 

 parasites gain the mastery. The first is generally observed in 

 mature Daphnice, which, although capable of infection, do not com- 

 monly take it ; the second in young individuals which generally 

 succumb to the parasite. 



Metschnikoff connects these results with some observations on 

 the diseases caused by fungi in the higher animals. 



* Ber. Deutscli. Bot. Gesell., ii. (1884) pp. 129-44. 



+ Arch. f. path. Anat. u. Physiol., xcvi. (1884) p. 177. See Naturforscher, 

 xxvii. (1884) p, 232. 



