SERA-FISHERIES LABORATORY. BAD 
the experiment. At the same time, the secretion of the 
substance from the walls of the sac ceases, and the remains 
of the style are pushed into the stomach by the action of 
the cilia. 
Barrois’ own view, based chiefly on the chemical 
composition of the style, 1s that it is a cuticular structure 
secreted by the wall of the sac, which acts as a lubricating 
material and invests sharp particles of sand, &c., with a 
viscous coating which prevents damage to the intestinal 
wall. As it is formed it is moved forward into the cavity 
of the stomach, where its free extremity is continually 
being worn away by the attrition of the food particles and 
the solvent action of the digestive fluids. The viscous 
fluid so formed also unites the food matter into a coherent 
bolus which easily traverses the intestine. 
The view that the style is a cuticular structure secreted 
by the wall of the pyloric caecum seems rather difficult to 
reconcile with the appearance of that epithelium, for, 
with the possible exception of the longitudinal strip of 
elongated cells in the caecum, the wall of the latter does 
not present the appearance usually associated with a 
secretory surface. The compact layer of columnar cells, 
the refractile free border, and the dense layer of long 
stiff cilia contrast strikingly with the wall of the right 
division of the lumen of the straight portion of the gut, 
where secretion into the cavity of the intestine is most 
probably taking place, and is far more suggestive of a 
surface performing a mechanical function than of an 
actively secreting epithelium. And it seems unnecessary 
to locate the mucus-secreting epithelium in the wall of 
the crystalline style sac. All along the course of the 
intestine there is abundant evidence of some substance 
being poured out into the lumen, in the rounded homo- 
geneous bodies found in the wall or projecting from the 
