1895.] The Crystallization of Cellulose. 21 
pharina, calotermes and julus. Among the molluscs he ob- 
tained the cellulose reaction in sepia, the pen of loligo, the 
radula of helix and the opercula of several species of natica. 
Theskeletons of rhizopod gthe prot , the perisarc 
of hydroids among the coelenterates, the tubes of annelids 
such as onuphis and polyodontes and also the skeletons of 
bryozoans among Vermes, gave no indication of the presence 
of cellulose. 
Without attempting to verify all of Ambronn’s results, I 
worked on a number of animal tissues, first trying the iodine test 
for cellulose on various parts of different arthropods and mol- 
lusks and then with such tissues as the skeleton of horny 
sponge, integument of the starfish and nereis, and vertebrate 
dermal tissues such as hair, skin, and nails. Inthe mollusksthe 
pen of loligo and radula of paludina, and among the arthro- 
pods the integument of the abdomen of eupagurus, the stalk 
of lepas, gills of limulus, and tests of ascidians such as salpa, 
molgula and amaroecium, all gave results confirmatory of 
those of Ambronn. As was to be expected from the lack of 
mention of such a thing in the literature, the vertebrate tis- 
sues gave no indication at all of cellulose. 
I next applied Gilson’s test for the presence of cellulose to 
some of the above which gave the strongest color with chloro- 
zinc iodide, to see if I could obtain the blue-staining sub- 
stance in the form of crystallites. The pen of loligo gave an 
intense violet with chlorozinc iodide but keeping for fifteen or 
twenty days in Schweizer’s fluid did not decrease the intensity 
of coloration when the sections were stained with chlorozinc 
lodide afterward, nor could any crystallites be obtained by 
a 
Precipitating with ammonia. 
In the same way the tissues of eupagurus, molgula and pal- 
udina were tried and all gave results like that in the case of 
loligo, the blue-coloring substance not seeming to be dis- 
solved out but remaining as at first uniformly diffused through 
the tissues. 
€ occurrence of the blue coloration in so many of the 
truly chitinous animal tissues suggested the idea that chitin 
°r some derivative of it might givethe bluecolor. The method 
of preparation of glycosamine by Ledderhose resembles in 
S€veral steps that of Ambronn for the demonstration of cel- 
lulose in animal tissues. I therefore (although a blue stain- 
ing with the iodine reagents had not been mentioned as one 
