Experiments were conducted to study the relationship of seed piece size to yield in potatoes and the following results obtained: 1. Large seed pieces produce a greater number of sprouts, a greater yield, and a larger number of tubers per hill as compared to the small seed. The size of the individual tubers is reduced in case of large seed pieces, whereas it is increased with small seed pieces. 2. Keeping the size of the seed tuber constant, it has been found that yield and other characteristics of tubers produced are influenced by the number of sprouts per hill. 3. Size of seed piece within the range of 10 to 40 grams, with one sprout to each seed piece, has no effect on yield and other tuber characters. 4. Large seed pieces give higher yields because of their capacity to produce more sprouts per hill. 5. Determinations of the chemical composition of seed tuber tissue at three stages of growth of the potato plant show that there is a comparatively more rapid depletion of stored food material from the small seed piece than from the larger ones. As this depletion does not affect yield, it is presumed that the amount of stored food material in the seed tuber, or seed piece size, has no relation to yield. These results also indicate that with an increased number of sprouts to each seed piece, there is more demand on the stored food material of the seed tuber.

The inheritance of linkage relations of tall vs. short plants and high vs. low number of rachis internodes were studied in relation to two known marker gene pairs in chromosome I of barley, non-six-rowed vs. six-rowed spikes (Vv) and awnless vs. awned outer glumes (Ee). Plant height was found to be governed by one main gene pair, Hh, and a modifier pair, H1 h1. However, Hh could be satisfactorily isolated so its linkage relations could be studied. Rachis internode number also was conditioned by one main gene pair, Rin rin, and a modifier pair, Rin1 rin1. Furthermore, Rin rin could be isolated for a study of its linkage relations. The order and recombination percentages of the four genes were found to be v - 17.1 - rin - 12.8 - h - 8.1 - e. The addition of rin and h to the map of chromosome I increases the number of mapped genes to nine which occur in the order tr - v - rin - h - e - y - f - lg - or.

A 5-year study of seed setting based upon number of seeds per head was carried out with a strain of early, double-cut red clover. The natural blooming period of the crop was greatly extended by a series of cutting treatments made at weekly intervals during June, which postponed the time of blooming of their respective aftermaths until successively later periods of the summer. Tagging of heads was carried out at approximately 2-days intervals at each of which at least 60 heads were tagged on plots in bloom as a result of the various cutting treatments. When the seeds ripened they were threshed out by hand and counted. The seasonal trend of seeds per head, although varying somewhat from year to year, showed rather low seed setting in the first growth. gradually declining to a marked low level during late June and early July then rising to a maximum in late July and early August. The seasonal and yearly trends of seeds per head agreed fairly closely with those of numbers of bumble bees for the same periods reported earlier. Under the conditions of this study it was concluded that the number of bumble bee visitors was a much more important factor in seed setting than number of honey bee visitors or number of florets per head. Aftermath crops of red clover brought into full bloom during late July or early August have a much better chance of receiving satisfactory pollination than the first growth blooming earlier in the season or aftermath crops brought into full bloom at a later date.

Comparative chemical analyses were made of diploid and tetraploid perennial ryegrass. In field rows, tetraploid plants were lower in percentage dry matter and higher in sucrose and total sugars and in the proportion of dry matter soluble in alcohol. In similar plants grown in culture solutions in the greenhouse similar results were obtained, except that tetraploid plants were lower in percentage dry matter only in respect to younger clippings and were higher in sugars only in more mature clippings. In white clover, octoploid plants were lower in fiber and in carotene than tetraploid plants. Differences in chemical composition which were found associated with an increase in chromosome number, while of statistical significance in those cases stated, were not however of great magnitude. In general, it may be stated that an increase in chromosome number was frequently associated with an increase in moisture and in the soluble constituents and with a decrease in the structural constituents. The reverse association was not found in any case.

<abstract language="eng">The A. refers that, in his last study, in his last studying trip to Colonia Santa Fé, Minas Gerais State, last month of March (autumn), had captured many wild flies (all from Tachinidae family, according to various entomologists of the Instituto Oswaldo Cruz), on a leprotic ulceration of the left leg of a lepromatous case of leprosy. The microscopical examination of the abdominal material from sch flies proved the presence, in rather great number, of HANSEN bacilli and a fungus of the genus Empusa COHN 1855. The A. intends to continue, next summer, such interesting research.