Gall-flies sentence example
- The views of Adler as to the alternation of generations of numerous gall-flies have been fully confirmed, it having been ascertained by direct observation that the galls and the insects produced from them in one generation are entirely different from the next generation; and it has also been rendered certain that frequently one of the alternate generations is parthenogenetic, no males being produced.
- In certain gall-flies (Cynipidae) no males are known to exist at all, and the species seems to be preserved entirely by successive parthenogenetic generations.
- All the other families of Hymenoptera, including the gall-flies, ichneumons and aculeates, have the first abdominal segment closely united with the thorax, the second abdominal segment constricted so as to form a narrow stalk or " waist," and legless larvae without a hinder outlet to the food-canal.
- The Cynipoidea include the gall-flies and their parasitic relations.
- They are the " gall-flies," many of the species laying eggs in various plant-tissues where the presence of the larva causes.Advertisement