It has been shown that Atropa belladonna acts as a symptomless carrier of Hyosoyamus Virus I. Some symptoms caused by this virus on other solanaceous plants are described.

A naturally occurring virus complex in Hyoscyamus niger was found to consist of Solanum Virus I (potato virus X) and Brassica Virus I. During the course of the investigation it was found that potato virus X forms local lesions on the cotyledons of ridge cucumber without systemic infection and that Brassica Virus I behaves similarly on the inoculated leaves of Nicotiana sylvestris.

1. The composition of the perienteric fluid of Ascaris lumbricoides of the pig, immediately after removal from the host and after varying periods of in vitro starvation, is recorded.

2. Apart from the more frequently observed constituents of invertebrate tissue fluids, the body fluid of Ascaris was found to contain ascorbic acid, amino sugar and small amounts of uronic acid.

3. Large amounts of anion other than chloride, probably fatty acid, must have been present in the body fluid, though chloride was probably the predominant anion in fluids of parasites which had passed several days of in vitro life.

4. The chief factors (starvation, osmotic pressure and the nature of the medium, etc.) affecting the composition of the body fluid are briefly discussed.