Canon W. H. T. Gairdner

? W H A T I S . . . a Projective Structure ?

The theory of locally homogeneous geometric structures on manifolds is a rich playground of examples on the border of topology and geometry. While geometry concerns quantitative relationships between collections of points, topology concerns the loose qualitative organization of points. Given a geometry (such as Euclidean geometry) and a manifold with some topology (such as the round 2-sphere), ...

ELECTRON MICROSCOPE OBSERVATIONS ON INTRACELLULAR VIRUS-LIKE PARTICLES ASSOCIATED W ITH T H E CELLS OF T H E LUCKt~ RENAL ADENOCARCINOMA* BY DON W. FAWCETT, M.D

Relatively few malignant neoplasms have been described in amphibia. The one that has been studied most extensively is the Luck6 renal adenocarcinoma of the frog, Rana pipiens. This malignant tumor occurs in from two to four per cent of frogs of this species, collected in the Lake Champlain region of northern Vermont and adjoining areas of Quebec. In a series of papers Luck6 described its histop...

Dr W. H. Hylton

Dr William H. Hylton, formerly a general practitioner in Clevedon died suddenly on March 20th at the age of 83. William Hawkins Hylton?Bill, was born in Leeds in 1906. He was educated at Bridlington College. His father ran a building firm but died tragically of acute appendicitis when his son was aged 14. Bill intending to pursue the same career entered Leeds University and took a degree in eng...

OBSERVATIONS W I T H T H E ELECTRON MICROSCOPE ON T H E SOLVATION AND RECONSTITUTION OF COLLAGEN BY PARKER VANAMEE,* M.D., A~rD

Electron microscope studies of collagen have dealt, for the most part, with the morphology of the mature or completely formed fibers.' I t has been shown that fibers from a variety of sources have the same characteristic periodic structure which consists of regularly spaced bands of greater density to electrons, arranged crosswise to the long axis of the fibers. The combination of a dense (A ba...

Dr. W. H. S. Walker