1. The thyroids of the adult Californian newt, Triturus torosus, were examined in Zenker, Champy, and Nassonov preparations, in one series in which these glands were entirely at rest, in another series in which they underwent a spontaneous activation and in a third group in which activation had been forced by intraperitoneal injections of thyroid activator.
2. As in invertebrates so in the newt the Golgi apparatus appears to consist of two components, of one which is deeply blackened, and of another one which stains much darker than the cytoplasm and corresponds to Bowen's idiosomatic substance. The former frequently forms a shell around the latter as a core. The problem has been discussed in the light of the work published recently by Owen and Bensley.
3. Only incomplete observations are available concerning a possible relation between Golgi apparatus and functional phase of the cell.
(a) In the resting condition the Golgi apparatus is relatively small and compressed in an apico-basal direction.
(b) In preparation for colloid release through the basal cellends, the Golgi apparatus enlarges greatly in an apico-basal direction and its trabeculae become stout.
(c) In the cells in which fluid has accumulated in large lacunae and is excreted through the basal cell-ends, the Golgi apparatus begins to become fragmented into long, slender pieces.
(d) In the cells in which basal excretion has ceased and the remaining liquid has been condensed into stainable droplets, the fragments are transformed into short, thick, and lumpy pieces.
(e) When the colloid droplets are redissolved and transformed into vacuoles for the purpose of refilling the follicles, the Golgi bodies appear as black rings around a dark core.
4. In most instances the topographical relation existing between the Golgi apparatus and the secretion products is not specific. The distribution of the Golgi material represents merely an accurate repetition of the distribution of the cytoplasm.
5. In some instances, however, a close relationship is found between the Golgi apparatus and the secretion products (figs.12-15, 22, 23, PI. 36).
6. In no case does the Golgi apparatus show a reversal of its position from the apex to the base of the cell. In cells which are in an active state of basal excretion the Golgi apparatus may be strictly apical. Its position does not convey a knowledge of the excretion polarity of the cell.
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