716 CHARLES PAUL ALEXANDER 



9 millimeters in length, but grows rapidly during the spring, attaining 

 its full size (17 millimeters) in two months of growth. Liogma glabraia 

 spends the winter as a very small larva, but in the spring its growth is 

 greatly accelerated. 



The haunts in which the larvae of crane-flies occur are exceedingly 

 varied. In the case of single large genera, such as Dicranomyia and 

 Tipula, the species range from those that are almost strictly aquatic to 

 others that are entirely terrestrial, living in decaying wood or even mining 

 in the leaves of plants. 



The transition between strictly aquatic and terrestrial forms is very 

 gradual, as was pointed out by Miall (1895:11) some years ago when 

 he wrote: 



How did insects ever come to seek the water, seeing that their mode of respiration is 

 primarily adapted to another element? We can see almost all the steps of the adaptation 

 on the shores of our rivers, lakes and seas. We can see dipterous larvae which, like the 

 " leather jacket " (the larva of the daddy-long-legs), burrow in the ground for their vegetable 

 food, and devour the roots of grasses. Other larvae of the same family (Tipulidae) prefer 

 moist earth in the neighborhood of streams. Others again live immersed in water, or mud 

 saturated with water, though they come to the surface at times and push their tails, which 

 carry the spiracles, into the air. Some few have become so completely aquatic that they 

 seldom, if ever, come to the surface, and all their supply of oxygen is obtained from the 

 water. 



The culmination of this latter condition is reached in forms such as 

 Antocha and related genera and species. Crampton (1919:100) has 

 made similar observations on the subject. 



The haunts of the larvae of crane-flies are best shown by the following 

 table, in which the various species are arranged according to habitat, 

 from the strictly aquatic to the various terrestrial forms: 



Habitat Species 



Strictly aquatic, in silken cases Antocha 



In very rapid water (lotic) on or in sub- Dicranomyia simulans, Pedicia, Triogma, 

 merged mosses (hygropetric association) Tipuline No. 1, and others 



Aquatic, on submerged plants Phalacrocera, Triogma 



Semi-aquatic (part of life spent in water, Dicranomyia simulans, Eriocera, Hexatoma, 

 but pupation taking place on land) Aeshnasoma, Longurio, Tipula abdomi- 



nalis, T. caloptera, TV bella, and others 



On cliffs and wooden walls, usually hi silken Dicranomyia simulans, Geranomyia, Ellip- 

 cases covered by water tera, Dactylolabis, and others 



In cold springs Pedicia, Thaumastoptera 



