Developmental Abnormalities in Drosophila Melanogaster Induced by Ultraviolet Radiation

In a number of previous papers we have reported on modifications in the morphogenesis of Drosophila melanogaster Meig. by x-irradiation, neutron bombardment, and under adverse environmental conditions. Additional data concerning the problems involved are found in the papers of workers in the same field, who have used the same or different methods of approach (Patterson, 1929; Geigy, 1931; Henshaw, 1933; Richards and Furrow, 1925; Jones, 1936; Russel, 1940; Hartung, 1942; Lawrence, 1937; Combs and Gravett, 1937; Mavor, 1927; Bardeen, 1910; et al). A comparison of various methods used in the study of these questions show that the differences in the results obtained depend largely on the following factors: genetic constitution of the organisms used in the experiments, nature of the agent used to modify development, stage of development during which the agent was active and environmental conditions during and after the exposure

A Lead Destroying Ant from Panama

During the winter of 1947 the telephone line of a police station in the city of Balboa, Canal Zone, suddenly went dead. The station was serviced by an underground cable encased in a lead pipe of three quarters of an inch in diameter. Workmen began to dig up the cable and after a prolonged search found the cause of the disturbance. A colony of ants had attacked the lead shell of the cable, had severed it effectively in one place and had cut deep notches in several other places. In addition large areas of the lead sheathing had been peeled off by the insects and the cable had been scored deeply in other places

Metachromasia in the Hearts of Human Embryos and Fetuses

The matrix of certain mammalian tissues contains several types of sulfated and non-sulfated mucopolysaccharides (cf. Meyer, 1948) in addition to other carbohydrates (cf. GIegg et al, 1954), cement substance and fibrils. One of the non-sulfated mucopolysaccharides, i.e., hyaluronic acid, has been demonstrated in connective tissue, in teeth, in brain tissue, in the intervertebral discs, bovine vitreous humor, synovial fluid, the lung and other tissue. (Bairati et al, 1952; Bensley, 1950; Friedman, 1953; Holland, 1954; and others). The mucopolysccharides are depolymerized under certain conditions by specific enzymes; thus hyaluronic acid is depolymerizcd by the spreading factor (Duran-Reynals, 1928), the Eizytoplasma auflosende Substanz (Yamane, 1935), the sperm enzyme (Pincus and Enzmann, 1936). Chain and Duthie, 1940, have claim~d that all these substances are identical and have renamed them hyaluronidase

Woitkowskia, a New Genus of Army Ants

The present paper deals with a new genus of army ants whose males seem to constitute a connecting link between the genera Eciton Latreille and Cheliomyrmex Mayr. The new genus Woitkowskia may put Eciton and its subgenus Neivamyrmex in a direct line of phylogenetic relationship with the genus Cheliomyrmex, and through the Cerapachyini with the Ponerine ants. The author assumes that Neivamyrmex and the new genus are closer to the ancestral stem of the Doryline ants than the more highly specialized subgenera Eciton s.str. and Labidus; the possible relationship of these ants is expressed in the appended diagram