210 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
of experiments carried out on Mytilus, from which it 
appears that not only is the style absorbed during the 
starvation of the animal by keeping it in filtered sea-water, 
but it is formed anew on abundant food being supplied. 
Haseloff inferred that the style ‘‘is the product of the 
chemical transformation of the excess of food material 
taken in by the animal, the change being effected by the 
agency of the digestive ferments.’’ More lately, Woodward* 
working on the same mollusc, was able to confirm Haseloff’s 
experiments. 
Barrois rejects the conclusion of Hazay and Haseloff, 
basing his objections chiefly on the chemical composition 
of the style which is very different from that of most reserve 
food materials, and on the unusual form in which the 
substance is stored up. In both these points it differs 
notably from all undoubted physiological reserves. In 
Helix pomatia, which undergoes a true hibernation, abun- 
dant reserve food material is stored up in the liver in the 
form of glycogen. This substance undergoes a gradual 
change into sugar in the course of the hibernation period, 
and ultimately disappears completely. Moreover, neither 
in Mytilus nor in Cardiwm taken during all times in the 
year was he able to observe any change in the volume of 
the style. Specimens of Cardiwm were placed in filtered 
sea-water and starved for eleven days. Only after the 
elehth day was any diminution in volume observed, and in 
general complete disappearance only occurred on the death 
and partial decomposition of the animal. The disappeayr- 
ance of the style during this experiment Barrois regards 
as due, not only to the solution of its substance in the 
stomach which goes on, as under normal conditions, but 
also to the profound bodily disturbance brought about by 
“On the Anatomy of Pterocera, with some notes on the crystalline 
style. Proc. Malacological Soc., London. Vol. I., pt. 4. 1894, 
