. The biology of dragonflies (Odonata or Paraneuroptera). Dragon-flies. 36 THE IMAGO [CH. 2. Zygoptera. The males have a pair of superior appendages (sup) homologous with those of the Anisoptera. Likewise, these also form the anal appendages of the female, which are usually extremely reduced cylindrical or conical stumps. The inferior appendages of the Zygoptera are, however, two in number, and have nothing in common with the so-called "inferior appendage" of the Anisoptera. They lie latere-ventrally below the anus, one on either side, and represent the cerci of the larva; that is, t
. The biology of dragonflies (Odonata or Paraneuroptera). Dragon-flies. 36 THE IMAGO [CH. 2. Zygoptera. The males have a pair of superior appendages (sup) homologous with those of the Anisoptera. Likewise, these also form the anal appendages of the female, which are usually extremely reduced cylindrical or conical stumps. The inferior appendages of the Zygoptera are, however, two in number, and have nothing in common with the so-called "inferior appendage" of the Anisoptera. They lie latere-ventrally below the anus, one on either side, and represent the cerci of the larva; that is, they are outgrowths from the reduced bipartite sternite of the eleventh segment. The laminae anales are placed as in the Anisoptera. The female, as in the Anisoptera, has no inferior appendages, though Heymons has shewn the existence of their rudiments in Calopjieryx. The diagram, fig. 12 B, shews the positions of the various Fig. 16. Position of the anal appendages of the male in Zygoptera during pairing. ° A in Austrolestes analis Ramb., b in Pseudagrion aureofrons TUlyard. a ante- rior; b median; c posterior lobe of prothorax; cx^ procoxa; ex, mesocoxa; h hook; inf inferior appendages; ml mesostigmatic lamina; sup superior appendages; 9-10 abdominal segments. Original. In the Zygoptera, during the process of pairing (fig. 16), the appendages of the male engage the prothorax and the back of the head of the female, in quite a different manner from that described for the Anisoptera. In this case it is the hind lobe of the pronotum which becomes engaged between the jaws of the vice, the head only being touched when the inferior appendages are long enough to pass forward and press against it from behind (as in some Lestinae). If the superior appendages are forcipate, a simple transverse lock- grip (fig. 16 a) behind the pronotum appears sufficient to hold the female, bearing in mind the fact that the latter always assists by pressing the pronotum backwards against the spi
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