1. The only cytoplasmic inclusions visible in the living neurone are lipid globules and mitochondria.

2. In both Helix and Limnaea there are three kinds of lipid globules, as follows:

(a) large globules, yellowish from their carotinoid content;

(b) smaller globules, easily coloured by vital dyes;

(c) small globules, not colourable by vital dyes.

The crescents and rings (‘dictyosomes’) seen in ‘Golgi’ preparations appear to be formed by the deposition of silver or osmium on the distorted contents of the smaller globules that are easily coloured by the vital dyes.

4. No crescents or rings are seen in the cytoplasm of the living cell.

5. The mitochondria are long, thin threads.

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