Nitrogen catabolism in nematode parasites.

Nematodirus /ilicollis, Nematodirus spathiger, and Ascaridia galli were maintained for periods of 24 hours in' a non-nutrient medium containing streptomycin and penicillin to prevent bacterial growth. UnEler aerobic 'conditions the total soluble nitrogenous material excreted by Nematodirus spp. in three experiments was 1.23-1.59 mg. nitrogen per g. dry wt. of tissue. Peptide nitrogen accounted for 33-37 per cent. of the total soluble nitrogen excreted, ammonia nitrogen 40-42 per cent., and urea nitrogen 11-17 per cent. Small amounts of uric acid werc found. Under similar conditions the total soluble nitrogen excreted by Ascaridia gaUi was 0.29-0.41 mg. per g. dry wt.; of this, 14-15 per cent. was due to peptide nitrogen, and 8 per cent. to urea nitrogen. No uric' acid was found.