SEVENTEENTH ANNUAL REPORT. 



383 



closely related to the mites which produce scab, mange, and itch. 

 Acarines may be divided into the following families: 



No tracheae, 

 epimeres. 



Legs with 



Body elongated. — Vermiformia. 



Two pairs of legs. 1 



Palpi unarmed. |Phytoptid8e. 



Mandibles styliform. J 



Four pairs of legs. 1 



Palpi uncinate. >Demodicid8e. 



iMandibles stvliform. J 



B. — Body compressed. — Acarina. 



(Palpi joined at base 



L,egs witn epimeres. 



[Sarcoptidae. 



Tracheae opening in the an 

 terior portion of the body 

 atrophied in the aquatic< 

 forms. Prostigmata. Legs 

 with epimeres. 



Tracheae opening in the pos- 

 terior portion of the body, 

 at the base of the legs, 

 sometimes atrophied. 

 Metasf igmata. Legs with- 

 out epimeres. 



armed. 



[Mandibles chelate. 



Palpi free, unarmed; anten 



niform. 



Mandibles chelate. 



Palpi free, armed. 



Mandibles with hooks, 



styliform. 



Palpi free, fusiform, mandi 



bles chelate. 



Palpi free, filiform or valvate. . 



>Argasidae: Ixodidae. 



Mandil)les, pseudo-chelate 

 Palpi free, filiform. 

 Mandibles chelate. 



|Bdellid£e. 



(Marine: Halacaridae. 

 Fresh water: Hydrachnidae. 

 Terrestrial: Trombidiidae. 



Oribatidae. 



Gamasidae. 



Superfamily Ixodoidea^ Banks, 1894. 



From the table of s3^nonvm3^ given in the footnote, it will be seen 

 that there has been considerable difference of opinion relative to the 

 systematic rank to be given to this group, the latter having been recog- 



^Syxonymy and Bibliography 



1804: Fam. Ricinife (in part) Latreille, 1804, pp. 46-53.— Idem, 1829, pp. 286-289.— 

 Risso, 1826, pp. 180-184 (pars).— Oudemans, 1896, pp. 191-197. [See also 

 Trouessart, 1891, p. 290.] 



1815: Fam. Ixodkles Leach, 1815, pp. 396-399.— Fuller, 1896, p. 763. 



1837: Fam. Ixodea Burmeister, 1837, p. 579. — Grube, 1859, p. 455. — Gerstaecker, 

 1860, p. 464. 



1847: Order JSicm? Koch, 1847, pp. 5-136. — Furstenberg, 1861, p. 208. — Canestrini, 

 1890, p. 482. [See also Trouessart, 1892, p. 298.— Marx, 1892, p. 232.] 



1855: Fam. Ixodida Kuchenmeister, 1855, pp. 421-424. — Kolenati, 1857, pp. 19-24. 



1863: Fam. Ixodidae Gerstaecker, 1863, pp. 343, 344.— Conil, 1877, pp. 28, 29.— Glaus, 

 1880, p. 652.— Michael, 1884, p. 50.— Berlese, 1855, p. 131.— Ludwig, 1886, 

 p. 612.— Riley, 1887, pp. 744, 745.— Marx, 1892, p. 232.— Trouessart, 1892, 

 pp. 28, 33, 37, 38, 45, 46, 47.— Neumann, 1892b, pp. 94, 95-105.— Railliet, 1893, 

 pp. 631, 703-718.— OsBORN, 1896, pp. 255-262.— Morgan, 1899, pp. 136, 141.-- 



