268 
NOTES AND MEMORANDA. 
of cells by means of small, highly refractive granules, while the 
central cells are joined to each other and to the enlarged cell ; in this 
manner, a common plasmodium is formed, strewn with a consider- 
able number of nuclei. The germinal vesicle begins to degenerate, 
and disappears entirely (this last phenomenon agrees with the obser- 
vations of Kleinenberg) ; but the nuclei of the central cells undergo a 
transformation of another sort ; they increase somewhat in size and 
degenerate into fatty bodies ; at the same time certain of them divide 
(their nucleoli also take part in this division). The degeneration of 
a nucleus begins by a considerable increase of its nucleolus, which 
becomes highly refractive and ends by being blended with the con- 
tents of the nucleus. It is these degenerated nuclei, probably serving 
for the nutrition of the embryo, which Kleinenberg takes for pseudo- 
cells. The peripheral elements of the agglomeration, strewn with 
granules of a chitinous origin, serve to form the shell or the envelope 
of the ovum. 
In comparing my observations with those of Kleinenberg, I conclude 
that the German savant has taken the peripheral cells of the agglo- 
meration for a blastoderm, and the mass of central cells for an etfect 
of segmentation of the ovum. According to my observations. Hydra 
evidently cannot be regarded as an animal destitute of ef)ithelium : 
my former researches have established the fact that this epithelium is 
muscular.” * 
The Staining and Preparation of Bacteria. — In the ‘ Zeitschrift 
fur Mikroskopie’ Dr. W. A. Haupt explains his views as to how the 
staining and preparation of bacteria may be facilitated. 
After referring to the development in recent times of the doctrine 
of a contagium vimm, and the fact that scarcely a medical periodical 
can be taken up but we meet with articles on the etiology of infec- 
tious diseases with reference to bacteria. Dr. Haupt complains that 
from the inexperience of the authors or their defective microscopical 
observations these articles tend rather to obscure than elucidate the 
subject. He instances a paper by Dr. Tschamer which appeared in 
the same journal, in which hooping cough is attributed to the pre- 
sence of the Ustilago 3Iaydis, and its oidium from Capnodium Gitri. 
Dr. Haupt maintains that the Ustilagince have not the oidium form, 
and that this parasite being found exclusively on maize, it is strange 
that the disease should flourish where there is no maize, and be rare 
where it is cultivated in abundance. It is far more probable, he 
thinks, that it is produced by a kind of Micrococcus similar to the 
Micrococcus diphthericus. The presence of spores and fungi in cases 
where there is no hooping cough is a fact known to everyone who 
has had much to do with the microscopical examination of the contents 
of the oral cavity, and, as a case in point. Dr. Haupt relates how, 
together with Micrococcus diphthericus, &c., he found spores of Tilletia 
caries in the pus taken from a boy who was suffering from diphtheria. 
These, he concluded, had nothing to do with the disease, but were 
attributable to the atmosphere in which the boy lived being impreg- 
* ‘Comptes Reudus,’ vol. Ixxxvii. p. 412. 
