222 FOOD OF INSECTS. 



by its pedicle to the beetle, each of the remainder being similarly connected 

 with the one that precedes it; so that the nutriment drawn from the 

 beetle passes to the last through the bodies and umbilical cords of the 

 individuals which are intermediate. 1 Some have regarded these bodies as 

 true eggs ; and their analogy with the pedunculated eggs of Trombidium 

 aquaticum, which also seem to derive nourishment from the water-boatmen, 

 &c., to which they are fixed, and still more the circumstance of their ulti- 

 mately losing their pedicle and detaching themselves from the infested 

 beetles, give plausibility to the idea. Yet these animals are certainly fur- 

 nished with feet, and have, according to De Geer 2 , a part resembling a 

 mouth characters which cannot be attributed to any egg. 



In the variety of their instruments of nutrition, which you must bear in 

 mind are often quite different in the larva and perfect states, insects leave all 

 other animals far behind. In common with them, a vast number (the orders 

 Coleoptera, Hymenoptera, and Orthoptera, and the Iarva3 of Lepidoptera, 

 some Diptera, &c.) are furnished with jaws, but of very different construc- 

 tions, and all admirably adapted for their intended services ; some sharp, 

 and armed with spines and branches for tearing flesh, others hooked for 

 seizing, and at the same time hollow for suction; some calculated like 

 shears for gnawing leaves, others more resembling grindstones, of a 

 strength and solidity sufficient to reduce the hardest wood to powder : and 

 this singularity attends the major part of these insects, that they possess 

 in fact two pairs of jaws, an upper and an under pair, both placed' horizon- 

 tally, not vertically ; the .former apparently in most cases for the seizure 

 and mastication of their prey; the latter, when hooked, for retaining and 

 tearing, while the upper comminute it previously to its being swallowed. 



To the remainder of the class of insects, a mighty host, jaws would have 

 been useless. Their refined liquid food requires instruments of a different 

 construction, and with these they are profusely furnished. The innume- 

 rable tribes of moths and butterflies eat nothing but the honey secreted in 

 the nectaries of flowers, which are frequently situated at the bottom of a 

 tube of great length. They are accordingly provided with an organ exqui- 

 sitely fitted for its office a slender tubular tongue, more or less long, 

 sometimes not shorter than three inches, but spirally convoluted when at 

 rest, like the mainspring of a watch, into a convenient compass. This 

 tongue, which they have the power of instantly unrolling, they dart into 

 the bottom of a flower, and, as through a siphon, 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 my- 

 self, 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 composed of three distinct tubes the two lateral ones cylin- 

 drical 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 

 lateral tubes ; which grooves, by means of a most curious apparatus of 

 hooks like those in the laminae of a feather, inosculate into each other, and 



i De Geer, vii. 123. 2 Id. ibid. 126. 



