Volume 42, Issue 1
July 1955, pages 1-38
pp 1-13 July 1955
Eggs and beetles ofTrogoderma granaria proved highly resistant to extreme conditions of relative humidity.
In particular some oviposition and egg development were observed even at and close to 0% R.H. This feature enablesT. granaria to develop in very divergent microclimatic conditions such as in germinating grain in breweries in Europe, and out of doors in heaps of grain in Upper Egypt and in primitive grain stores in Punjab.
pp 14-26 July 1955
pp 27-30 July 1955
1. Most of the neurosecretory cells of the brain ofIphita limbata have a high concentration of acid phosphatase in their cytoplasm. Some cells do not show the enzyme in the cytoplasm. The nuclei of the ordinary brain cells contain acid phosphatase, but those of the neurosecretory cells show comparatively smaller amounts. The neurosecretory cells of the metathoracic ganglion also contain this enzyme.
2. The cytoplasm of the neurosecretory cells of the brain contains cholinesterase.
3. Alkaline phosphatase and succinic dehydrogenase are absent in the neurosecretory cells of the brain.
pp 31-38 July 1955
The ability of some species ofPseudomonas from marine environments to use single amino acids and other nitrogenous compounds as sole source of nitrogen was studied. Arginine, choline, cystine and glutamic acid were available for all cultures. Tyrosine, phenylalanine and tryptophane were also utilized by a large number of cultures. Valine, glycine and histidine were poor sources of growth but asparagine and urea were better. Two groups of apparently identical cultures such as ‘A’ and ‘B’ (Ps. marinodenitrificans) and D and G were each shown to be different species by virtue of the differential utilization of amino acids. The strictly ‘marine’ species was more exacting in its requirements and utilized few if any single amino acids. For denitrification, citrate was better as hydrogen donor than was glucose. It is possible to differentiate two apparently similar cultures by the pattern of amino acid utilization.