. The Cambridge natural history. Zoology. FIG-INSECTS 547 Eiley has called attention ^ to some facts in connection with /. tritici and /. grande, that make it clear that these two supposed species are really alternate generations, and that both generations are probably in larger part, if not entirely, parthenogenetic. Some species of the genus Megastigmus are known to be of phytophagous habits.^ The most interesting of all the forms of Chalcididae are perhaps those called fig-Insects. A considerable number of species are now known, and amongst them we meet with the unusual phenomenon of specie
. The Cambridge natural history. Zoology. FIG-INSECTS 547 Eiley has called attention ^ to some facts in connection with /. tritici and /. grande, that make it clear that these two supposed species are really alternate generations, and that both generations are probably in larger part, if not entirely, parthenogenetic. Some species of the genus Megastigmus are known to be of phytophagous habits.^ The most interesting of all the forms of Chalcididae are perhaps those called fig-Insects. A considerable number of species are now known, and amongst them we meet with the unusual phenomenon of species with wingless males, the females possessing the organs of flight normally developed. The wingless males exhibit the strangest forms, and bear no resemblance whatever to their more legitimately formed partners (Fig. 358, A, B). Many of the fig-Insects belong to a special group called Agaonides. Others belong to the groi;p Torymides, which contains likewise many Chalcididae of an ordinary kind; possibly some of these may be parasitic on the Agaonides. Some of these Torymid fig- Insects have winged males, as is normal in the family, but in other cases winged and wing- less forms of the male of one species may be present. The most notorious of these fig-Insects is the one known as Blastophaga grossorum (Fig. 358), this being the chief agent in the custom known as capri- fication of the ctiltivated fig- tree. This process has been practised from time immemorial, and is at the present day still carried on in Italy and the Grecian archipelago. The Greek writers who describe it say that Fig. m.âBlastophaga grossorum. A, ,, -1 1 /2 J. i-i V -J- ^ââc Male, X 22; B, female, x 15. (After the wild fig-tree, though it does ^^^'^^^ ^Jrâ ^^^ g^^^^_ j^^^^^^ iii^ ;^882.) not ripen its own fruit, is ab- solutely essential for the perfection of the fruit of the cultivated fig. In accordance with this view, branches from the wild fig ^ Report of the. Entoimlogist, Dep. Agriculture, JVashingto
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
