The exciting cause of the hypertrophy, in the case of the typical galls, appears to be a minute quantity of some irritating fluid, or virus, secreted by the female insect, and deposited with her egg in the puncture made by her ovipositor in the cortical or foliaceous parts of plants.
As the nut grows the slight puncture becomes almost obliterated, so that it is unnoticed by all but the most observant eye.
The tubes have walls thicker at the ends than in the middle, as the tendency to puncture the glass is greatest at the edges of the coatings.
Persica, on which it is produced by the puncture of an insect during the month of August.
Two years later he first tried the effect of electro-puncture of the muscles on a patient under his care, and from this time on devoted himself more and more to the medical applications of electricity, thereby laying the foundation of the modern science of electro-therapeutics.
Insemination takes place either by the introduction of the penis into the cloaca of the female, or by the puncture of the bodywall of the female by the penis, and the injection of the sperm into the body cavity, whence the single spermatozoa must make their way to the eggs.
This secretion is caused by the puncture of an insect, Coccus manniparus.
Many aphides, &c., puncture the leaves, suck out the sap, and induce va:ious local deformations, arrest of growth, pustular swellings, &c., and if numerous all the evils of defoliation may follow.
As a surgeon, Simon's work came second to his interest in sanitary science, but he claimed priority over Cock in the operation of perineal puncture of the urethra in cases of retention from stricture.
(3) Man is, in the majority of cases, infected through the skin, though the puncture may not be seen.
(Cattle food.) The adult weevils puncture the young flower-buds and deposit eggs; and as the grubs from the eggs develop, the bud drops.