. An introduction to zoology, with directions for practical work (invertebrates). 356 INTRODUCTION TO ZOOLOGY inside the pockets, jerking themselves round so that they expose first one side and then another. The two com- monest species are Simulium sericeum and Simulium elegans. This pupa is always submerged, and yet the fly ^Imaso^ which is to emerge from it would be injured if wetted by water. It is very difficult to observe the process by which this danger is surmounted. Appar- ently, during the latter part of the pupal stage which lasts about two weeks, air collects under the pupal skin, s
. An introduction to zoology, with directions for practical work (invertebrates). 356 INTRODUCTION TO ZOOLOGY inside the pockets, jerking themselves round so that they expose first one side and then another. The two com- monest species are Simulium sericeum and Simulium elegans. This pupa is always submerged, and yet the fly ^Imaso^ which is to emerge from it would be injured if wetted by water. It is very difficult to observe the process by which this danger is surmounted. Appar- ently, during the latter part of the pupal stage which lasts about two weeks, air collects under the pupal skin, so that when this splits, the imago rises with this air-bubble, which is extended in an air-film clinging to the hairs on the surface of the body of the fly, and thus all danger of drowning is Family 4 : Tipdlidab (Daddy-long-legs or Crane-flies) The Tipulidae are Diptera with slender bodies, very long legs, and narrow wings, which are held well above the body when at rest, the second pair of modified wings or halteres being unusually large. The veining of the wings is also char- acteristic and is rather com- plex, especially near the free tips of the wings (Fig. 283). The Common Daddy-long-legs or Crane-fly. This insect is shown in Fig. 283, where the typical form of body, the narrow wings, large halteres, long legs, simple long antennae, and projecting palps with their characteristic long terminal joint, all are clearly visible. In all species of Tipula, the sexes can be distinguished by 1 I have never been Incky enough to see the emergence of the imago, though I have reared many. These statements are based on Verdat's observations, quoted by Professor Fig. 283.—The Spotted Crane-fly, male ( x 2).. 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 Lulham, Rosalie Blanche Jermaine. London,
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Keywords: ., bookcentury1900, bookdecade1910, bookpublisherlondo, bookyear1913
