ri;s 



INSECTA. 



rudimentary biting mouth parts, an indistinctly segmented thorax, 

 and an abdomen which usually consists of nine segments. 



Fam. Pediculidae. Lice. With fleshy proboscis-sheath armed with recurved 

 hooks, protrusible suctorial tube, and two protrusible knife-like stylets. The 

 antennas have five joints. The feet, which are adapted for clinging, have 

 hooked terminal joints. The eyes are small and not facetted. The animals 

 live on the skin of Mammalia, and suck their blood, and lay their pear-shaped 

 eggs in the roots of the hair. The young, when hatched, do not undergo a 

 metamorphosis, and the louse which infects the human head, is fully developed 

 and capable of reproduction in eighteen days. Pcdicultis capltis Deg. Head- 

 louse of man. P. restimenti Burm. (larger and of pale colour). Phthlrius 

 jmbis L. (tig. 471). 



Fam. Mallophaga (Anoplura) (Pelzfresser). Lice-like in form, with thn-e- 

 to five-jointed antenna-, and biting mouth parts, no fleshy proboscis, but a sort 

 of suctorial tube. They live on the skin of Mammalia and Birds, and feed on 

 young hairs and feathers, but also on blood. Trlcltodectes conh Deg. PJiih>jjfen/.<t 



anse-ris Sulz. Mi-nopon 

 Nitsch, M. piiUldiini 

 Nitsch. on fowls. 



Sub-order 2. Phy- 

 tophthires. * Rhyn- 

 chota with two pairs 

 of membranous wings. 

 The female is usually 

 apterous. The surface 

 of the skin is very 

 often covered with a 

 dense waxy deposit, 

 the product of cuta- 

 neous glands which 

 are placed in groups beneath warty prominences of the segments. 



FIG. 471. Phthiriits pubis (after Landoig) St, Stigma; 

 TV, Trachea. 



Fam. Coccidae (Schildlause). The large females have a shield-shaped body, 

 and are wingless. The males are much smaller, and have large front wings, 

 and sometimes also rudimentary hind wings. The fully-developed males 

 have no proboscis or piercing weapons, and do not take in nourishment, 

 while the unwieldy, often unsymmetrical females, which may even have lost 

 the segmentation, insert their long rostrum into the parenchyma of plants and 

 remain motionless. The eggs are deposited beneath the shield-shaped body 



* C. Bonnet, "Traite d'Insectologie," Tom. I., Paris 1745. 



J. F. Kyber, " Erfahrungeii mid Bemerkungen iiber die Blattlause. " Gcnitar's 

 Maya:, der Entomol. Tom. I., 1815. 



J. H. Kaltenbach, " Monographic der Familie der Pflaiizenlause." Aachen, 

 1843. 



R. Leuckart, " Die Fortpflanzung der Rindenlause." Archie fill- JVaturgexck., 

 1851). 



