On Sterility

Sterility

On the Sterility of Eye Ointments.

HARDLY a year passes without a publication on the sterility of eye drops or ofmethods of ensuring freedom from contaminants. On ophthalmic ointments, however, the literature is sparse. Fisher, Accousti, and Thompson (1943) found that ointments containing 5 per cent. "sulfanilamide, sulfathiazole, or sulfadiazine" in a water-dispersible base may become contaminated. Lehrfeld and Donnelly (1948) ...

Studies on Hybrid Sterility. II. Localization of Sterility Factors in Drosophila Pseudoobscura Hybrids.

HE causation of hybrid sterility has long been one of the unsolved T problems of biology. To date, probably the greatest advance in this field has been made by FEDERLEY who discovered a failure of the meiotic chromosome pairing in the sterile hybrids between moths of the genus Pygaera. This finding has since been amply corroborated by other investigators in sterile hybrids both in animals and i...

Theodosius Dobzhansky on Hybrid Sterility and Speciation.

It is a truth universally acknowledged thatGenetics and the Origin of Species, Theodosius Dobzhansky’s acclaimed 1937 book, launched the modern evolutionary synthesis, characterized by uniting the findings of genetics with the facts of natural history. Dobzhansky’s title deliberately contained Darwin’s, as the book discussed a problem broached but not solved by On the Origin of Species (Darwin ...

Studies on Self-Sterility. IV. Selective Fertilization.

INTRODUCTION .................................................................. 346 Discussion of the problem ..................................................... 348 Pollen-tube frequency distributions ............................................. 349 Influence of growth of compatible pollen tubes upon incompatible pollen tubes.. .. 352 SUMMARY AND DISCUSSION ....................................