326 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
quite new intercellular connections might be established by a new 
formation of collaterals and of protoplasmic expansions. 
As compared with the theory of networks, that of the free branching 
of cellular expansions capable of growth appears not only more probable 
but also more encouraging. 
Nerve-cord of Rays.* — M. v. Lenhossek finds that the nerve-cells of 
the spinal cord of Rays are much more similar to those of Amphibia 
than to those of Teleostei, while there are points of resemblance to the 
Reptilian cord. The most striking peculiarity is the fine protoplasmic 
marginal plexus, the morphology and physiology of which require 
further examination. 
Altmann’s Bioplasts.] - — Drs. L. and R. Zoja support a modification 
of Altmann’s theory, according to which protoplasm is a colony of ele- 
mentary organisms or bioplasts united by an indifferent matrix. They 
find peculiar little fuchsinophilous plastidules in all sorts of animal cells, 
characteristically disposed in the various types, and believe that the 
particles have a nutritive function in the cell. 
Degeneration of Cells and Nuclei.:]: — Herr L. Drfiner has studied 
the cause of certain forms of cellular degeneration. He begins with 
that observed in the testes of Salamandra maculosa during the summer 
months. As to the actual facts of the degeneration, he has little to add 
to what has been observed by Flemming and Hermann, but his interpre- 
tation is different, for he finds that the degeneration is due to a parasite. 
The same is true of the epithelial cells of the gut. More than one cell- 
parasite seems to occur; for the one which is responsible for the 
“ karyolysis ” described, the author proposes the name Micrococcidium 
caryolyticum. 
Specific Character of Cell-divisions.§ — Dr. D. Hansemann recently 
published a paper entitled “ Studien fiber die Specificitat, den Altruismus 
und die Anaplasie der Zellen,” in which he sought to show that the cells 
of various tissues show quite characteristic differences in their mitoses. 
In that paper all his observations related to the tissues of Man. Now, 
however, he has extended his observations to other organisms with 
similar result. Thus he has studied, in the larva of Salamandra macu- 
losa , the epithelium of the mylohyoid plate, the connective-tissue cells of 
the branchial lamellae, and the red blood-corpuscles, and finds that the 
mitosis of each kind of cell is specifically characteristic, as regards form 
and arrangement of the chromosomes, the position of the spindle, and 
the size of the centrosomes. 
Physiology of the Cell.]] — Dr. J. Demoor claims to have demon- 
strated for two well-marked and essentially different cases that there is 
a marked independence between the life of the protoplasm and that of 
the nucleus. The former is only manifested in the presence of oxygen, 
the latter goes on regularly in a medium which is insufficient to main- 
tain the active life of the protoplasm. Chemical reagents produce very 
* SB. Phys.-Med. Ges. Wurzburg, 1893, pp. 156-7. 
f Bend. B. 1st. Lombardo, xxiv. (1891 !) pp. 981-8. 
I Jenaische Zeitschr. f. Naturwiss., xxviii. (1894) pp. 294-327 (2 pis.). 
§ Arch. f. Mikr. Anat., xliii. (1894) pp. 244-51 (1 pi.). 
|| Arch, de Biol., xiii. (1893 [published 1894]) pp. 163-244 (2 pis.). 
