NO. 1382. 



THE ACARINA OR MITES— BANKS. 



97 



the ti.ssue, and is of the size of the mite. As the female prog-resses 

 she leaves behind her a row of from ten to forty large eggs and a 

 considerable amount of '"■frass."" The female, having deposited her 

 complement of eggs, dies at the end of her Inirrow. As the skin of 

 the host is alwa^'s wearing off, and constantly being renewed from 

 ])elow, the Qg^>^^ when ready to hatch, will be close to the surface, so 

 that the mites may readily escape. iVbove each burrow there is often 

 a little pimple, containing a watery fluid. There appears to be no 



"Fig. 1^4. — Sarcoptes in her Bt'RROW. and eggs. 



means of distribution from individual to individual except b}" contact. 

 Many of the species that are normally confined to one host can live 

 on other animals and on man. The eggs if kept moist may retain 

 their vitality for a week. 



There are but a few genera; the better-known ones may be tabu- 

 lated as follows: 



1 . Anal opening on the dorsum - 2 



Anal opening Ijelow 3 



2. On small mammals, not bats; third pair of legs in male without apical suckers. 



Notoedres 

 On bats; third legs in male with suckers Prosopoderfes 



3. Pedicel of suckers jointed; mandibles styliform and serrate near tip Fsoroptes 



Pedicel not jointed ; mandibles chelate 4 



4. No suckers to legs of females; parasitic on birds Cyiemidocojjtcs 



Suckers at least on legs I and II; parasitic on manunals 5 



5. Legs very short; in male the hind pairs equal in size; body usually short. Sarcojiffs 

 Legs more slender; in male the third pair is much larger than the fourth; Ixxly 



more elongate '> 



6. Female with suckers to fourth pair of legs Choriop1<'>< 



Female without suckers to fourth legs 7 



7. Hind part of male abdomen with two lobes Cuparinld 



Hind part of male abdomen without lobes Otodectes 



Sarcoptes includes the species parasitic on man, although some oth- 

 ers may also occur. The human species is S. scahei. This pest was 

 formerly more common than now, particularly in armies. The intol- 

 erable itching caused by the presence of these mites leads to wild and 

 Proc. N. M. vol. xxviii— 04 7 



