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The article presents biography of poet V.R. 'Bunny' Lang who lived a brief but extraordinary life from 1924 to 1956 including information regarding her early life and background, and her influential role in the Poets Theatre.

1. Comparisons were made between the livers of pregnant and non‐pregnant rats, all of which were fed on a ration of 20 g food per day.

1. Excess ribonucleic acid ('RNA') is defined as the difference between the RNA contents of livers of pregnant and non-pregnant rats. Large amounts of excess RNA are formed in the liver of the rat during the last week of pregnancy. Excess RNA is formed in the liver after removal, on the 14th or 15th day of pregnancy, of the foetuses, or foetuses and ovaries, or foetuses and adrenals, or foetuses, ovaries and adrenals, or pituitary, or pituitary and foetuses, or pituitary, foetuses and ovaries. Viable placentae must be present.2. Two fractions of RNA appear to be present in the liver cells of pregnant rats. One fraction varies linearly with the protein content of the liver cells, as does the RNA of non-pregnant rats' livers. The second fraction (excess RNA) is quite independent of the protein content of the liver cells but varies linearly with the weight of the placentae and the energy, but not the protein, content of the diet.3. Hypophysectomy lowers the amount of excess RNA by 20–25 %. After removal of the foetuses on the 14th day, the placentae do not attain the normal weight, and the amount of excess RNA is smaller than in normal pregnancy. After removal of foetuses and ovaries the placentae are larger and heavier than after removal of the foetuses alone.4. Both adrenalectomy and ovariectomy in non-pregnant female rats cause a small rise of liver deoxyribonucleic acid ('DNA') and RNA. After hypophysectomy, there is a loss in liver RNA greater than that expected from the simultaneous loss of liver protein. The loss of RNA occurs even when the loss of liver protein is prevented by feeding the rats by stomach tube. DNA is not lost from the liver a fortnight after hypophysectomy, as long as the energy intake is normal.5. In non-pregnant female rats oestradiol, but not progesterone, causes an increase of liver DNA and RNA. This is not found in hypophysectomized rats. Injection of an alkaline placental extract causes a significant rise of liver RNA which, however, is very much smaller than that found in pregnancy.6. Since hypophysectomy lowers, but does not abolish excess liver RNA in pregnant rats, it is concluded that at least two factors play a role: first and foremost, an unknown factor secreted by the placenta, acting independently of the pituitary, and second, increased amounts of oestrogen apparently requiring the presence of the pituitary.

Little is known of the changes occurring in the liver during pregnancy and lactation. The ratios of liver weight and liver protein to body weight are increased in pregnant rats [Bokelmann & Scheringer, 1932], and more of the maternal protein is apportioned to the liver in pregnant rats than in non-pregnant controls [Poo, Lew & Addis, 1939; Poo, Lew, Lee & Addis, 1940]. The total nucleic acid content is considerably raised, both deoxyribonucleic and ribonucleic acids taking part [Davidson & Waymouth, 1944]. There is an increase of the ascorbic acid content of the livers of mice and rats during pregnancy [Kennaway & Kennaway, 1944; Kennaway & Tipler, 1947]. The arginase content of the liver of rats is normal during pregnancy but increased during lactation [Folley & Greenbaum, 1947].Since during pregnancy and lactation the maternal organism has to provide the material for a very rapid protein synthesis, considerable changes in

1. The protein content of liver cells is almost independent of the size of the animal (mice, cats and previous results on rats, Campbell & Kosterlitz [1949]), and varies with the amount of protein eaten.2. As has already been shown for rats, the ribonucleic acid ('RNA') content of the liver cells of non-pregnant mice, guinea-pigs and cats varies directly with the protein content of the cells. For a given protein content the mouse and rat have more RNA than the guinea-pig and cat.3. During pregnancy there is a rise of the deoxyribonucleic acid ('DNA') content of the livers and in the protein content of the liver cells of mice (and rats), but not of guinea-pigs.4. An excess of RNA over that predicted from the protein content of the liver cell has previously been found for the rat during pregnancy, and ascribed to the action of a placental factor on the maternal liver. A similar excess of RNA has now been observed in the mouse and, to a less extent, in the guinea-pig. It appears to be absent in the cat.5. Possible causes of some of these species differences are considered.

One of the first observations which showed differences between the livers of male and female rats was that by Deuel, Gulick, Grunewald & Cutler [1934], who noted that the liver glycogen of normal adult male rats remained at a constantly higher level than that of females during periods of fasting up to 3 days. Deuel, Butts, Hallman, Murray & Blunden [1937] found that this sex difference was present also in non-fasted adult animals, while it was absent in immature and in senile rats. The decreased glycogen content of the liver of female rats was probably due to an inhibitory effect of the ovary.Korenchevsky, Hall, Burbank & Cohen [1941] found that the size of the liver cell is smaller in the female than in the male rat. Orchidectomy decreased both actual and relative liver weights and oöphorectomy the relative liver weight, in either case without significant change in the size

1. A negative correlation was found between the mean weight of an individual placenta and the number in a litter. Within the range examined and with the methods employed, no definite correlation between the mean weight of an individual foetus and litter size was established.2. Reduction of the food intake to one-half or one-third during the last 6 days of pregnancy did not result in a decrease in the number and weight of foetuses and placentae. This was apparently brought about by drawing on the maternal reserves laid down during the first 14 days of pregnancy. Absence of protein from the diet during the last 6 days resulted in a very moderate decrease in foetal and placental weights.3. Absence of the maternal adrenals or pituitary had no influence on foetal and placental weights. The decrease in maternal body weight after hypophysectomy was solely due to loss of appetite and could be prevented by giving the rats adequate amounts of food by stomach tube.4. The increase in body weight during the first 14 days of pregnancy was maintained after removal of the foetuses as long as the placentae survived. The placentae also had a favourable effect on the maternal body weight in the absence of the foetuses, when the ovaries or adrenals or the pituitary or the pituitary and ovaries were removed, but not when both ovaries and adrenals were absent. The placental factor responsible for this effect appears to act through the ovaries or adrenals.5. The increase in the weight of the ovaries during pregnancy was not affected by removal of the foetuses, foetuses and pituitary, or foetuses and adrenals. The adrenals of pregnant hypophysectomized rats were not heavier than those of non-pregnant hypophysectomized rats.

A biochemical and histological study was made of the livers of 12 ewes in late pregnancy, 18 post-parturient ewes, and 4 non-breeding ewes. Liver weight did not change significantly during pregnancy, but it increased in relation to the carcase weight, and there was an increase in the concentration of RNA in the tissues. After parturition, there were both hyperplasia and hypertrophy of the parenchymal tissue, and there were significant absolute increases in liver weight, and in the total contents of dry matter, protein, lipid, RNA and DNA. Large seasonal hypertrophic changes occurred also in the livers of non-breeding sheep.