TiruLiD^. 381 



pairs of long, horn}-, pointed valves." The larva; (Fig. 298, 

 natural size, a larva of this famih' found living under stones 

 iu a running brook at Burkesville Junction, Va. In the 

 American Naturalist, vol. ii, it was 

 referred to Tabanus) diti'er from 

 those of the neighboring families in 

 having but a single pair of spiracles Fis- 2: 8. 



at the anal end of the bod}'. The head is rather large, and 

 '' embedded nearly up to the mouth in the fli-st thoracic seg- 

 ment ; the mandibles are hornj'^ and strong, and forked at tho 

 end." The body is grub-like, of a unifoi'm grayish, brownish, 

 or whitish color, and consists of twelve segments. 



"The larvae of Ctenophora, living in wood, have a soft, 

 white, smooth skin, similar to that of the larvre of longicorii 

 beetles, or of the As Hi dee, living in similar conditions. 

 The larva of Tipula living in the soil, or the lan-ae of those 

 species of Ctenophora which are found in wood so far de- 

 composed as to be like soil or vegetable mould, have a much 

 tougher skin, and are covered with a microscopic, appressed 

 pubescence. This toughness, as Avell as some stiff bristles, 

 scattered over the surface of the skin, is probably useful in 

 burrowing. Thus the larva of Trichocera, digging in vegeta- 

 ble mould or in fungi, is covered, according to Ferris, with mi- 

 croscopic erect bristles. The larva of Ula, living in fungi, has. 

 according to the same author, still longer bristles. Those larva^ 

 living in water (as some Limnobina) are soft and slimy, of a 

 dirt}^ greenish color, and with a peculiar clothing of appressed 

 microscopic hairs, not unlike those of the larvae of Stratiomys. 

 The most anomalous of all the Tipulideous larvae are those of 

 the Cylindrotomina. That of Cylindrotoma distinctissima 

 lives upon the leaves of plants, as Anemone, Viola, Stellaria. 

 almost like a caterpillar. It is green, with a crest along the 

 back, consisting of a row of fleshy processes. The larva of 

 Cylindrotoma (Phalacrocera) replicata, according to Degeer, 

 lives in the water, on water plants, and is distinguished by nu- 

 merous filaments, which, although resembling spines, are flexi- 

 l»le and hollow on the inside. Degeer took them for organs of 

 respiration." (Osten Sacken.) 



The larvae move bv means of minute stiff bristles arising 



