. Economic entomology for the farmer and fruit-grower. Beneficial insects. 378 AN ECONOMIC ENTOMOLOGY. any evidence at present, there is a continuous breeding by female individuals only. There are only a very few injurious species among these gall- flies. Occasionally we find on blackberry stems an irregular, warty swelling, and if F^G. 435- this be cut into, it will be found full of cells occupied by these little Cynipid larvae. This kind of gall is known as '' multicellular,'' be- cause inhabited by nu- m e r o u s specimens. Similar galls are found on the roots of rose and plants of the sam
. Economic entomology for the farmer and fruit-grower. Beneficial insects. 378 AN ECONOMIC ENTOMOLOGY. any evidence at present, there is a continuous breeding by female individuals only. There are only a very few injurious species among these gall- flies. Occasionally we find on blackberry stems an irregular, warty swelling, and if F^G. 435- this be cut into, it will be found full of cells occupied by these little Cynipid larvae. This kind of gall is known as '' multicellular,'' be- cause inhabited by nu- m e r o u s specimens. Similar galls are found on the roots of rose and plants of the same natural family, and in a few other cases cul- tivated plants become subject to gall growths. As a matter of fact these galls are scarcely injurious, because in most cases the plant continues growing be- yond them, or even if a shoot is lost, perma- nent injury is rarely done. Certain species of oak-galls produce a black stain, and these were at one time al- most universally employed in making an ink of remarkable per- manence. Even yet the law in some States requires for certain records an ink of which oak-galls is one of the ingredients. It is a small step from parasitism upon vegetation to parasit- ism upon animals, and hence it is not surprising to find that some species of this family are parasitic on other insects. The differ- ences between these forms and the true gall-makers are not easily. a, Pithy gall on blackberry, made by LjmsirupJiui nebulosus; b, section to show cells; c, larva; d, Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Smith, John Bernhard, 1858-1912. Philadelphia and London, J. B. Lippincott company
Size: 1239px × 2017px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectbenefic, bookyear1906
