Crossword-Solution: THYROIDS 8 letters, 2 clues 🏆 scrabble score: 15

The crico-thyroids are the antagonists of the above-named muscles, and they may act either very much alone or, to some extent, in coöperation with the above, to regulate or steady their action; for in movements so complicated as those required for voice-production it is highly probable that we are inclined to reduce our explanations of muscular action to a simplicity that is excessive, and to appreciate but inadequately the delicacy and complexity of the mechanism and the processes involved.

The latter include the (_a_) crico-thyroids, which tense and elongate them, (_b_) thyro-arytenoids, which relax and shorten them.

This is in harmony with the following facts: (1) The crico-thyroids are the muscles most in use in ordinary speech and in singing the lower tones.

The subject is still hidden in darkness to the extent of insufficient knowledge on our part of the exact constituents of the active agents in the secretions of the testes, thyroids, suprarenals, pituitary and other glands.

Thyroids were removed from animals and after some time serum from these animals, supposed to be of lower thyroid content, was injected into human beings with the idea of reducing the hyperthyroidization or perhaps neutralizing it by some substance present in the serum.