170 W. WALDEYER. 
plasm,” and with Pfitzner’s “ parachromatin ;” it is the feebly- 
staining ground substance of the chromatic threads, in which 
the frequently mentioned deeply staining chromatin granules 
are embedded. We shall very easily become familiarised with 
the name “linin,’”? on account of its brevity, in place of 
the inconvenient terms ‘ nucleo-hyaloplasm ”’ and “ para- 
chromatin.”? Strasburger, indeed, has already adopted the 
word in his latest work. (8) ‘ Paralinin,” by which is meant 
the more fluid substance of the nucleus, which is present 
between the threads. Its synonyms are “ Kernsaft” (O. 
Hertwig), “Zwischensubstanz,’’ and “ Achromatin” (Flem- 
ming), and “ Karyochylema” (Strasburger). (4) “‘ Pyrenin” 
(zupny = nut, nucleus) refers to the substance of which the 
nucleoli are composed. It may reasonably be doubted, as 
is done, for example, by Strasburger (191), whether F. Schwarz 
is right in assuming a uniform substance for nucleoli. (5) 
“ Amphipyrenin,” the substance forming the nuclear mem- 
brane. This is very similar to pyrenin. (Cf. what is said 
about the relation of the nucleoli to the nuclear membrane.) 
Nevertheless, pyrenin takes stains easily, whilst amphipyrenin 
does not; both exhibit reactions different from chromatin. 
According to Schwarz, linin agrees most nearly with nuclein 
in its reactions, and not with chromatin (in opposition to 
previous views, see above). Paralinin stands close to globulin. 
This paralinin is not a fluid in the usual sense, therefore the 
otherwise suitable word “ Kernsaft” does not commend itself ; 
moreover, it is achromatic. One can only admit a true “sap,” 
like karyochylema, in vacuoles. As this view agrees with 
that of Carnoy already mentioned, we must inquire further 
into it. : 
In opposition to most of the recent views, F. Schwarz (185) 
holds that in cell-protoplasm there is no preformed net- 
work, but that a part of it can form itself into threads and 
strings ; that is, cytoplasma isa mixture in which, under certain 
circumstances, a separation of a denser, more tenacious, and of 
a more fluid substance can take place. For instance, vacuole 
formation is due to such a separation. As for the chemical 
