FOOD OF INSECTS. 395 



tinrolling, they dart into the bottom of a flower, and, 

 as through a syphon, draw up a supply of the delicious 

 nectar on which they feed. A letter would scarcely 

 suffice for describing fully the admirable structure of 

 this organ. I must content myself therefore with here 

 briefly observing that it is of a cartilaginous substance, 

 and apparently composed of a series of innumerable 

 rings, which, to be capable of such rapid convolution, 

 must be moved by an equal number of distinct muscles; 

 and that, though seemingly simple, it is in fact com- 

 posed of three distinct tubes, the two lateral ones cy- 

 lindrical and entire, intended, as Reaumur thinks, for 

 the reception of air; and the intermediate one, through 

 which alone the honey is conveyed, nearly square, and 

 formed of two separate grooves projecting from the la- 

 teral tubes ; which grooves, by means of a most cu- 

 rious apparatus of hooks like those in the laminae of a 

 feather, inosculate into each other, and can be either 

 united into an air-tight canal, or be instantly sepa- 

 rated, at the pleasure of the insect^. 



Another numerous race, the whole of the order He- 

 miptera, abstract the juices of plants or of animals by 

 means of an instrument of a construction altogether 

 different — a hollow grooved beak, often jointed, and 

 containing three bristle-formed lancets, which, at the 

 same time that they pierce the food, apply to each other 

 so accurately as to form one air-tight tube, through 

 which the little animals suck up'' their repast; thus 



^ For a full description of this instrument see Reauni. i. 125 &c. 

 Plate VI. Fig. 29, 30. 



^ The mode, however, ia which this is effected in all insects furnished 

 with a proboscis, can scarcely be by suction, strictly so called, or the abs- 

 traction of air, since the air-vessels of insects do not communicate with 



