H,— 29,

In February, 1935, five sick and one healthy sheep were also obtained in the Atiamuri District. They were given limonite iron-free extract, Eeyburn's limonite, Kenya iron oxide, Lux, and. zinc acetate. The healthy one was kept as a control. These were continued until January, 1936. The animal being fed Kenya iron oxide died, and the one on limonite extract made little progress. The two fed on Eeyburn's limonite and zinc acetate, respectively, made good progress. The sheep on Lux went back in condition, was changed to cobalt chloride, and then made good progress. In January more sheep were obtained, and three were given Eeyburn's limonite, three cobalt chloride, three zinc acetate, two purified iron ammonium citrate, and one limonite iron-free extract. One sheep on Eeyburn's limonite suffered from foot-rot and is just recovering. Two others, one on zinc and one on purified iron ammonium citrate, were lost while shearing. The available figures show that those on Eeyburn's limonite made satisfactory progress. Of those on zinc, two made slow progress and one went back in condition. The purified iron ammonium citrate was of no use at all, but the sheep on limonite extract has made some progress, while the sheep receiving cobalt all made significant advance. An explanation of the non-success with purified citrate of ammonium and iron is that iron salts may require traces of impurity to effect assimilation of iron by the animal analogous with the change induced by contact (catalysis) with traces of a third" compound in two chemical salts. Hence the improved condition of sheep when fed zinc, cobalt, arsenic, and possibly other metallic salts, may be owing to the influence of an element inducing the further assimilation of iron from the natural food or from medicinal iron administered. To summarize the position to-day it would seem that the wisest course for farmers to follow will be to continue to use as a stock lick approved limonite. This has been proved quite successful and cheap in the treatment not only of bush sickness, but also of other similar but complicated troubles such as Morton Mains disease in Southland and coast disease of South Australia. The utmost caution should be exercised in experimenting with such a potent element as cobalt, which has not yet cured deficiency diseases in a succession of generations of sheep, nor has it yet been proved to be an essential element in animal nutrition. For the present cobalt stands in the same category as arsenic and other poisonous stimulants which may cure bush sickness in the individual but not in the race. Pampas-grass (Coktadekia Selloana). Chemical Investigations. —Analyses by a variety of methods of the cellulose, hemicellulose, and lignin components of the pampas-grass have been carried out and the results published in an article on " The Composition of Pampas-grass " in the New Zealand Journal of Science and Technology, Vol. XVII, No. 3, pp. 528-30, 1935. It was shown that pampas has a high content of cellulose and hemicellulose combined with a comparatively low content of lignin, and it was considered that this would favour ready digestibility by the ruminant. Later work showed that the succulent leaf-bases which are greatly relished by cattle contained only 14-1 per cent, of lignin in the dry matter, compared with 2Olfper cent.fto 21-5 per cent, in the dry matter of the green leaf-blades. Analysis of material cut from a row of pampas-grass, transplanted as seedlings from Whangarei Harbour shows that the composition of this seedling material is very similar to that from the rootcuttings (offsets) originally experimented with in the Hauraki Plains.

Confirmatory evidence of the value of pampas-grass as stock-food when grown in other soils and locations than those of the Hauraki Plains is now available. In contrast with the poor strike of offsets (root-cuttings) obtained in many localities, particularly in dry weather, the small seedling plants sent out from Whangarei have in all cases so far reported grown with great freedom. Seed obtained from Whangarei and also from England has germinated well. The seed germinates best if only the thinnest covering of fine sandy soil be sifted over it, or even when merely laid on the surface of damp, sandy soil in a box with a glass cover in a warm shady place. A character of pampas-grass in which it differs from most other fodder crops is the ability to stand a high percentage of salt in the soil and the ease with which it colonizes reclaimed estuarial flats. As the reclamation of the many thousand acres of rich estuarial mud-flats at present of no value must form a part of any progressive land policy, pampas-grass for grazing and for planting on salty areas and for consolidating stop-banks will be most useful. lodine Investigation.' The analysis of a great many glands already in hand has been proceeded with. A paper on the iodine survey of the Canterbury District is in the press.

66

g . Reducing Sugars. I] II I 11 If If I Alh " p «I I 24th December, 1935 .. 24-2 0-53 20-5 45-5 0-82 1-01 8-58 6-88 0-34 0-31 12th March, 1936 .. .. 27-2 0-56 20-6 39-6 2-17 5-06 11-52 8-75 0-32 0-31