ORTIIOPTERA. 



561 



they have cast their pupal skin, probably copulate after they return from their 

 flight to the nest, and then lose their wings, retaining only the basal stump. 



The males remain behind in the community, as according to the works of 

 Smeathman, Lespes, Bates, etc., a king is said to remain always in the com- 

 pany of the queen. After copulation the queen, which remains in the com- 

 munity, swells up to an enormous size on account of the enlargement of her 

 ovary, and begins to lay the eggs frequently in special places in the nest. 

 They are at once carried away by the workers. Termcs lucifugus Ross., South 

 Europe. T.fatale L., in tropical Africa, builds hills from 10 to 12 feet high. 

 Calotcrmcs flavicollis Fabr., South Europe. 



Tribe 3 : Amphibiotica. 

 tracheal ills. 



The larvae live in water and possess 



Fam. Perlidae. Body elongated and flat, with laterally placed eyes, three 

 ocelli and setiform antennas. The wings are 

 unequal, and the posterior region of the broad 

 hind wings can be folded downwards. The 

 abdomen has ten segments and two long 

 segmented filaments. The wings arc often 

 reduced in the males. The female carries the 

 eggs for a time in a depression of the ninth 

 abdominal segment, and finally deposits them 

 in water. The larvae live beneath stones. 

 They usually have tracheal gills on the thorax, 

 and feed principally on the larvae of Epliemc- 

 ridfs. Jfeniiira ncbulosa L., Pcrla bicavdafa 

 L., P. (Ptcronarcy) reticulata Burm., with 

 tufted gills. Found in Siberia. 



Fam. Ephemeridae. May flies. Body slender, 

 and soft-skinned, with hemispherical eyes, 

 three ocelli and short setiform antennas. The 

 front wings are large, the posterior small and 

 rounded, sometimes fused with the anterior or 

 altogether absent. The mouth parts are rudi- 

 mentary. The males have very long front 

 legs. The abdomen has ten segments and 

 terminates with three long anal filaments, of 

 which the median one may be absent. The 

 penultimate abdominal segment of the male FlG - ^.-i 

 has two jointed copulatory forceps. The May 

 flies live only a short time in the winged stage, taking no nourishment and 

 devoting themselves entirely to the business of reproduction. We often find 

 swarms of them in the air on warm summer evenings and the next morning 

 see their dead bodies lying in quantities on the ground. The larvae live at the 

 bottom of clear water and feed on other insects. They have a large head with 

 powerful mandibles and toothed maxillae. On the abdomen they bear six 

 to seven pairs of swinging plates, which function as tracheal gills, and at the 

 end of the abdomen they have three long feather-like caudal setae. The larvae 

 moult frequently (in Chloeon more than twenty times) and, according to Swam- 

 mcrdam, require three years for the passage into the winged insect. After the 

 ecdysis of the pupal skin, which is provided with the rudiments of wings, the 



36 



v.Jgafa 

 animal); Af, Anal filaments. 



