1036 The American Naturalist. [December, 
the glands were first examined as to the nature of the reaction 
of this secretion, and this was found to be slightly acid since 
it produced a tinge of red in a neutral solution of litmus. This 
trace of acidity, however, was found to be due to some organic 
acid, since a neutral solution of tropaeolin 000, which is ex- 
tremely sensitive to mineral acids, showed no change in color 
upon the addition of a small piece of the freshly crushed 
glands. 
II, Examination for Leucine. 
For the extraction of leucine, should any be present, the 
glands of several star-fishes were macerated with water and 
allowed to stand for some time. After filtering through 
cheese-cloth the filtrate was acidulated with acetic acid and 
boiled. A considerable coagulum of native albumen appeared, 
which was filtered off, and to the filtrate lead acetate added. 
The small precipitate was filtered off and sulphuretted hydro- 
gen passed through the filtrate to remove the excess of lead. 
This precipitate was removed by filtration and the filtrate then 
evaporated to dryness. The residue was extracted with boil- 
ing alcohol, filtered and evaporated to a syrup. On standing, 
knots of crystals collected on the sides of the beaker which 
showed, by microscopic examination, the characteristics of 
very impure leucine. They could not, however, be certainly 
identified as such, since their quantity was insufficient to try 
Scherer’s test. In all probability, however, if this method 
were applied to a number of glands sufficient to give a con- 
siderable yield of crystals, they could be purified and would 
undoubtedly prove to be leucine with probably some clusters 
of tyrosin. 
B. Proor or tHE Non-ExIstENCE OF GLYCOGEN. 
In determining whether the function of the pyloric cæca of 
the star-fish is more similar to that of the liver or to that of 
the pancreas of higher animals, one of the most reliable crite- 
ria would be the existence or non-existence of glycogen in the 
organ. 
Therefore the ceca of about twenty living star-fishes were 
quickly removed and placed in boiling water where they were 
