290 Seifriz . — - Observations on some Physical Properties of 
He there (14, p. 367) describes the ‘ living jelly ’ as a ( transparent, glutinous 
substance, insoluble in water ’ (‘ cette substance glutineuse, diaphane, ; 
insoluble dans l’eau’), and further (14, p. 368) emphasizes ‘its insolubility in 
water * as one of the properties which distinguish it from ‘ substances with 
which it might be confounded such as ‘ albumin, which it resembles in its 
mode of coagulation But one does not have to go back nearly a century 
for authoritative evidence on the immiscibility of protoplasm. Hertwig 
(19, p. 13) speaks of protoplasm as a ‘viscous, almost always colourless, in 
water-immiscible substance ’, and Biitschli (7, p. 543) says, ‘ Since the fact 
exists . . . that protoplasm is not miscible in water . . .’ These statements i 
are probably the outcome of direct observations on the behaviour of proto- 
plasm in water. Such observations can be readily made by aid of micro- 
dissection. ; 
If an ovum of the sea-weed Fitcus or of an echinoderm is torn by 
microdissection needles, one of three things will happen : the egg will most 
often heal the wound with little or no loss of protoplasm ; occasionally it i 
will burst at the first touch of the needle and the egg contents scatter with 
the violence of a miniature explosion (37, p. 316) ; rarely will the proto- : 
plasm flow out and mix with the surrounding water. In the last two cases 
the escaped cell content is miscible, but it is then no longer real living 
protoplasm, for those peculiar properties which make protoplasm a living 
substance are lost. If the tear is so large that much of the protoplasm 
escapes, this escaping protoplasm will usually round up into droplets with 
no indication of mixing with the water. The dissection of many dozens of 
marine ova supports this statement. To cite but one instance — the dissec- 
tion of some twenty eggs of the sea-urchin Tripjieustes resulted in two 
cases of rapid miscibility, and these were both of eggs which showed other j 
signs of degeneration such as previous excessive imbibition. The rate and 
percentage of spoiling among marine ova is rather great. These degenerate 
eggs go to pieces readily. Frequently, a healthy egg will exhibit great 
resistance and tolerate a surprising amount of dissection. For example, 
one Tripneustes ovum withstood several minutes of dissection, during which 
time the protoplasm was kneaded, torn, and droplets of it pinched off. 
There was no indication of miscibility until apparently the ‘ organization ’ 
of the protoplasm finally completely broke down, and general disintegration 
set in, with, of course, loss of individuality of the cell— -that is, of those j 
properties which make of the cell an organized living unit. 
The same behaviour characterizes the protoplasm of myxomycetes. 
Plasmodia can be punctured, torn, stretched, droplets pinched off, and fresh 
surfaces of the peripheral hyaloplasm or the inner granular plasma exposed 
to the surrounding water, and nineteen times out of twenty the wound is 
healed. 
The same treatment of Amoeba will more often result in loss of proto- 
