ARTICULATA. 147 



upon the bcack and breast, and in the clothing of unclean persons. It is 

 more slender, with a thinner neck than P. capitis^ and its eggs are attached 

 to the hair of the breast and arms. It is common npon the lower classes in 

 Eussia and Spain. P. tahescentiuni infests the body also. It resembles P. 

 capitis and P. vestimenti, but is a little larger, the head romid, the thorax 

 qnadrate, the abdomen ending with four bristles, the antennae rather long, 

 and the color pale yellow. It inhabits the human body in the folds of the 

 skin, and is found in connexion with the disease named Phthiriasis. It 

 forms small scale-like flaps of the skin, beneath which it is found, particu- 

 larly upon the back, breast, and neck. Among those who have died of this 

 disease were Antiochus Epiphanes, Herod, Plato, the emperor Maximian, 

 and the poets Alemanus and Ennius. Burmeister thinks this species has a 

 spontaneous origin in the corruption of the fluids in old or enervated sub- 

 jects. He states that it is not contagious, as a woman of seventy who 

 occupied a bed with her husband did not communicate it to him. This 

 case was cured by the application of oil of turpentine. Cleanliness is of no 

 avail, new lice being in some cases produced until the death of the patient. 

 See Burmeister's Manual of Entomology, English ed., p. 307, § 203 ; and 

 Kirby's Bridgewater Treatise, chap. 1. The human race is attacked by 

 still another and smaller species of parasite, which difters so much from the 

 former one, as to constitute a distinct genus named Phthirius {P. pubis, 

 ft. ^il^fig. 76). The body of this species is short and wide, and the thorax 

 much wider than the head. It infests the axillary and inguinal regions. 



Fam. 2. JSfirmidce. These insects are chiefly found infesting birds, and 

 are familiarly termed bird lice. The head is generally large and triangular, 

 rounded in front, and often with pointed projections ; the mouth is beneath ; 

 the labrum, labium, mandibles, and maxillse are present, the last being in 

 most cases minute, and either with or without palpi. AVhen the palpi are 

 present, they have four articulations. These insects do not feed upon blood, 

 but the feathers upon which they are usually foimd seem to supply them 

 wdth food. A bird may have from one to five species of these lice ; and 

 the same species sometimes inhabits several distinct birds, but in general 

 certain forms are confined to certain orders and families of them. 



The genus TricTiodedes of Nitzsch belongs to this family, and is found 

 upon Mammalia, as the dog, cat, weasel, bear, porcupine, horse, ox, sheep, 

 deer, &c. Gyropus also infests Mammalia. The most useful single work 

 upon this order is Denny's Monographia Anoplurorum Britannia, London, 

 1842, 8vo., with 26 colored plates. 



Order 3. Siphonostoma. This name was proposed for the fleas {Piilex, 

 and several allied genera) by Latreille, in 1825 ; Kirby and Spence named 

 them Aplianiptera, in 1826 ; Degeer named them /6'wc^ori«, 1778 ; and some 

 restrict the term Aptcra to them. The mouth approaches nearer to that of 

 the higher Diptera, with which order they have the greatest affinity, and in 

 which they would probably be placed by Burmeister. Fleas are parasitic 

 in their perfect state, infesting man, beasts, and birds. Tlie body is com- 

 pressed, with a tough shining integument, and transverse rows of bristles. 

 There are no wings, but these organs are represented by two scales on 



351 



