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changed through force of circumstances; and as a summary of the shepherds' diary notes as to illness, miscarriage, failure to breed, deaths, and the fostering-off of lambs. This system at first is arranged to duplicate the original grouping of all ewes as they occur in their breeding paddocks, and just as a change may be necessitated in the field through, say, an infertile sire, so is the grouping of these miniature cards made to correspond in the laboratory. The 1942 Progeny Tests.—ln the first two months of 1943 the body and wool descriptions and measurements recently collected from the seven hundred and fifty yearling progeny wei'e examined. These data were then assembled for the progeny tests of sires and were transferred to the card recording system, where the lifetime records of each breeding-ewe are kept—one card for each ewe. The 1943 Mating.—These cards, having been brought up to date, now included the measurements—past and present—of fleece weights and hairiness, and the evaluations of body and other wool characters. Such measurements and evaluations in course of time have now come to refer to both parents as well as their progeny as yearlings. It is from such records of performance that decisions are made as to what sheep or sheep families to cull, and what are the most hopeful lines upon which to mate the dams of dam families of the experimental stud. Guided, therefore, by previous performances, the suggested matings were then pencilled in on each card, thus facilitating collaboration with the owners in finally determining the matings, in sire marking and in splitting into mating mobs the entire stud of over one thousand ewes. Present and Future Objects.—Here it should be explained that the immediate object of this systematic mating on the basis of performance is to build up a stud of such a quality that sires (and dams) will be found eligible to pass on from the progeny test to the more exacting close-breeding test, the results of which are judged and recorded on lines similar to those just described. Further, the close-breeding test, when successfully passed, leads on to the formation of a nucleus flock, closed to sheep outside the family—where genuine prepotency for desired vital and commercial characters is intensified. Work at Present in Hand.—Evidence is accumulating as to the success attending this building-up process within the experimental stud, and progeny tests of twenty-six sires, based on the body and wool characters of about seven hundred and ninety yearling progeny, are nearing completion. Pig Research Professor W. Biddet Previous work reported on efforts being made to study the inheritance of length in pigs has been continued. Inbred and line-bred strains of long and short type of purebred Tamworth pigs have been bred and raised. This has been carried out in order to fix types so that the effects on length of reciprocal crosses can be closely studied in successive generations. With a view to making progress as rapidly as possible in improving the length of the long strain, several sires are being progeny tested. This is a somewhat tedious process when only about ten sows can be maintained, but it is considered that it is the soundest method of effecting improvement. As in past years, breeding results have been measured by the careful measurement of the carcasses of the progeny of pigs under observation when carried to baconer weight of approximately 200 lb. Continuing previous work on the introduction of desirable genes of the Large White breed to the Tamworth, first-cross Large White-Tamworth sows were mated to a Large White boar and progeny of the back cross were inter-bred. The first litters from these back crosses arrived in January, 1944, and though it is too early to state what precise influence this method of breeding may have on our objective,'the results expressed in the weaner pigs appear to be promising. Variations in colour of the crossbred pigs are providing valuable material for the study of inheritance of colour in pigs. This side of the work is being followed up by Dr. Dry, of the college staff. However interesting the colour results are, care is being taken not to let the colour studies interfere with the main objective of improving the length of carcass side and thickness of hams. Root-development Work Mr., W. A. Jacques Unfortunately, due to difficulties in securing labour, experimental work on this project has been suspended. It may therefore be a suitable time to review the scheme as a whole and indicate progress, together with a summary of work to be completed. The work was commenced in 1935 and a paper read to the New Zealand Grassland Conference on " Some Preliminary Observation on Fertilizer Placement in Relation to Root Growth in Some Grasses." The position regarding fertilizer placement for grasses was there outlined and a number of problems that were of importance to this country were dealt with. The preliminary work was conducted at the same time as that on crested dogstail was being concluded. The first trial was concerned with the effect on rye-grass of the intensity and time of defoliation on the root bulk and penetration. As a practical outcome of this, the effect of taking a hay crop in the first year of establishment was determined. Samples were being taken periodically on autumn- and spring-sown plots in an effort to determine how the roots behave, particularly before and during the onset of dry weather. A technique for root sampling and washing was evolved and has been used wherever it has been necessary to obtain comparisons of root bulk. While it has worked reasonably satisfactorily, it is considered that further improvements could be made. At the same time that root sampling was in progress, profile drawings were made to obtain a more complete picture of root form.

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