42 



THE INSECT WORLD. 



of the larvae of the gnat (Fig. 28). They are very small, and 

 come to the surface of the water to breathe ; for which purpose 

 they extend the opening of a pipe, A, which is attached to the 

 last segment of the body, a little above the surface. They 

 are, consequently, obliged to hold their heads down. By the 

 side of the breathing-tube is another tube, B, shorter and thicker 

 than the former, nearly perpendicular to the body, its^ orifice 

 being the exterior termination of the digestive -tube. At the 

 anus it is fringed with long hairs, having the appearance, when 

 in the water, of a funnel. At the end of 

 the same tube, and inside the hair funnel, are 

 four thin, oval, transparent, scaly blades, hav- 

 ing the appearance of fins. They are placed 

 in pairs, of which one emanates from the right 

 side, the other from the left. 



These four blades or fins have the power 

 of separating from each other. Each segment 

 of the abdomen has on both sides a tuft of 

 hair, and the thorax has three. The head is 

 round and flat, and is provided with two 

 simple brown eyes. Round the mouth are 

 several wattles, furnished with hair, of which 

 two of crescent-like form are the most con- 

 spicuous. These tufts move with great quick- 

 ness, causing small currents of liquid to flow 

 into the mouth, by means of which the necessary food, microscopic 

 insects and particles of vegetable and earthy matter, is brought 

 to the larva. 



They change their skin many times during their continuance 

 in this state. This latter fact has been remarked by Dom 

 Allou, a learned Carthusian, "whose pleasure," says Reaumur, 

 "consisted in admiring the works of the Almighty, when not 

 occupied in singing his praises/' We think it will be inte- 

 resting to repeat the few lines which accompany the mention 

 made by Reaumur of this worthy Carthusian. They appear to us 

 to be well worth reading even at the present day. 



" If the pious monks who compose so many societies, possessed, 

 like Dom Allou, the love of observing insects, we might hope 



Fig. 28. Larva of the 

 Gnat. 



