The mouth leads into the oesophagus, which extends straight down the body nearly to the aboral end or " ampulla," where it dilates into a stomach, from which the ascending limb of the U-shaped alimentary canal passes directly to the anus.
So far is it from being an haemostatic that, if perfused through living blood-vessels, it actually dilates them.
Now we can see the reason for their administration, because the nitrous ether, consisting chiefly of ethyl nitrite, dilates the superficial vessels and thus allows greater escape of heat from the surface; while acetate of ammonia, by acting as a diaphoretic and stimulating the secretion of sweat, increases the loss of heat by evaporation.
The pack has the double effect of restraining his movements and thus lessening the production of heat, while at the same time it dilates the vessels of the skin and produces loss of heat.
By division of the egg-cell a mulberry-mass of embryonic-cells is formed (morula), which dilates, forming a one-celllayered sac (blastula).