100 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXVIII. 



feather.s, others produce a crust of loosened tissue and dead skins 

 similar to that of Norwegian itch. They may begin on the comb or 



skin of the feet, but gradually spread down 

 the neck or up the legs. The species are all 

 short and l)road, w^ith short legs and with 

 very few hairs above, and these small. They 

 give birth to living six-legged larva?, which, 

 however, appear to have hatched from eggs 

 while in the body of the parent. C. mutaiis 

 Rol)in is the itch mite of domestic fowls, at 

 times a very serious pest. The disease it 

 produces is known as ''scaly leg," since the 

 mites are most al)undant on the legs. The 

 best remedy is to soak the legs in warm 

 soapy water until the crusts are loosened; 

 then apply sulphur ointment. Bathing the 

 affected portions in a 5 to 10 per cent solu- 

 tion of creolin is also a good remedy; the 

 treatment should be repeated in a few days. 

 The infested fowls should be isolated until 

 cured. Another species, 0. galling Railliet, 

 occurs at the base of the feathers, where 

 it burrows and produces a mass of loosened 

 scales. The itching induces the hens to 

 pluck their feathers. 



Fig 



189. — P.SOROI'TES COMMUNIS, 

 VAR. OVIS, MALE. 



Family CYTOLEICHID^E. 



This family {Sarcoj^tides cysticoles of Megnin) contains but two 

 species — Cytoleiolius (formerly Cytodltes) nudnik and Lanihiosioptes 

 (often Symplectojytes) cydicola — both of 

 economic importance. They were dis- 

 covered in 1870 by Francesco Yizioli 

 in the common fowl. Both are very 

 small, soft-bodied mites, much like a 

 Sarcojptes^ but differing in having the 

 vulva longitudinal and the smaller and 

 less prominent mouth-parts. The legs 

 are ver}^ short, the anterior pairs the 

 larger, and all separate at l)ase. The 

 tarsus ends in a long sucker, but with- 

 "out claws. LaDihumlojjtts sometimes 

 occurs on the skin, but often bores into 

 the sulicutaneous tissue, where it gives 

 rise to a calcareous cyst. Cytoleiclnia fi«. ioo.-cvtoleichis kudus. 

 has l)een found in various parts of the common fowl, l)ut most 

 commonly in the air-passages and air-cells. Here its presence in 



