THE LOUSE. 97 



also men of renown, among whom Denny in his work on the 

 Anoplura, or lice, of Great Britain, mentions the name of "Phe- 

 retima, as recorded by Herodotus, Antiochus Epiphanes, the 

 Dictator Sylla, the two Herods, the Emperor Maximian, and 

 Phillip the Second." Schioclte, in his essay " On Phthinus, and 

 on the Structure of the Mouth in Pediculus" (Annals and Maga- 

 zine of Natural History, 1866, page 213), says that these state- 

 ments will not bear examination, and that this disease should be 

 placed on the " retired list," for such a malady is impossible to 

 be produced by simply blood-sucking animals, and that they are 

 only the disgusting attendants on other diseases. Our author 

 thus describes the mouth parts of the louse. 



"Lice are no doubt to be regarded as bugs, simplified in 

 structure and lowered in animal life in accordance with their 

 mode of living as parasites, being small, flattened, apterous, 

 myopic, crawling and climbing, with a conical head, moulded 

 as it were to suit the rugosities of the surface they inhabit, 

 provided with a soft, transversely furrowed skin, probably 

 endowed* with an acute sense of feeling, which can guide them 

 in that twilight in which their mode of life places them. The 

 peculiar attenuation of the head in ffont of the antenna? at once 

 suggests to the practised eye the existence of a mouth adapted 

 for suction. This mouth differs from that of the Hemiptera 

 (bed-bug, etc.) generally, in the circumstance, that the labium is 

 capable of being retracted into the upper part of the head, 

 which therefore presents a little fold, which is extended when 

 the labium is protruded. In order to strengthen this part, a flat 

 band of chitine is placed on the under surface, just as the shoe- 

 maker puts a small piece of gutta-percha into the back of an 

 India-rubber shoo ; as, however, the chitine is not very elastic, 

 this baud is rather thinner in the middle, in order that it may 

 bend and fold a little when the skin is not extended by the 

 lower lip. The latter consists, as usual, of two hard lateral 

 pieces, of which the fore ends are united by a membrane so that 

 they form a tube, of which the interior covering is a continu- 

 ation of the elastic membrane in the top of the head ; inside its 

 orifice there are a number of small hooks, which assume differ- 

 ent positions according to the degree of protrusion ; if this is 

 at its highest point the orifice is turned inside out, like a collar, 

 whereby the small hooks are directed backwards, so that they 

 can serve as barbs. These are the movements which the animal 

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