XVII. Observations respecting several British Species of Hieracium.

Interaction between Some Pasture Species and Two Hieracium Species

Possible control options are investigated for the introduced Hieracium weeds, particular problems in South Island high country, New Zealand. In a pot experiment regression of input to output ratios of above ground biomass over successive harvests, from binary mixtures was used to determine the competitive interaction between 13 pasture species and two Hieracium species, H. pilosella and H. prae...

Hieracium sinoaestivum (Asteraceae), a new species from North China

Hieracium sinoaestivum Sennikov sp. nov. is described as new to science and illustrated. This presumably apomictic species is solely known from two old collections made in a single locality in the Shanxi Province of China. It belongs to the hybridogenous group Hieracium sect. Aestiva (Hieracium sect. Prenanthoidea × Hieracium sect. Umbellata) and is most similar to Hieracium veresczaginii from ...

Smoking: Ten Years' Observations of British Doctors

In previous papers (Doll and Hill, 1954, 1956) we have described how at the end of October 1951 we sent a short and simple questionary to the 59,600 men and women whose names were on the current British Medical Register and who were then resident in the United Kingdom. In addition to giving name, address, and age, they were asked to say whether (a) they were, at that time, smokers of tobacco, (...

Composition of Eggs of Several Bird Species

--This paper presents the lipid, nonlipid dry matter, and water contents of the eggs of the Starling, Coturnix Quail, Mourning Dove, Laughing Gull, and Mallard and compares the data with published accounts of the eggs of other species. The lipid level of the yolk and the percentage of yolk in the egg increase in direct relation to the precocity of the young at hatching. The high lil•id content ...

Characteristic Electrophoretic Patterns of serum protein of Several species of snakes of Iran