ACARUS. 



ACARUS. 



seventh joint is furnished with a cordiform 

 membranous caruncle, and a single simple 

 claw or hook ; rostrum and legs reddish. 



This species is viviparous and oviparous, 

 and the eggs very numerous. The larvae 

 are hexapod. 



These mites are very abundant upon old 

 cheese, the powder of which entirely consists 

 of them, with their eggs and excrement. 



Ac. lonyior. Body and hairs longer. 

 Found upon Gruyere and Dutch cheese 

 (PI. 6. fig. 2). This is the so-called Ac. 

 Crossii. 



Ac. Siculus. With short legs. Found in 

 powdered Cantharides. Megnin, p. 143 ; 

 Murray, p. 274. 



Ac. mycophagus. Body long. Found 

 on mushrooms. Megnin, p. 143. 



Ac. entomophayus. Found in collections 

 of insects, of which it devours the body. 

 Megnin, p. 143 j Murray, p. 263. 



Ac. mains. On apple-trees in N. America. 

 Murray, p. 275. 



Ac. translucens. On coffee-plants in 

 Ceylon. Murray, p. 275. 



Ac. bicaudatus. Abdomen furnished with 

 two pedif orm tubercles, beneath the base of 

 each of which is a stigma. Found upon 

 the feathers of an ostrich. 



Ac.fari'na, same SisA.domesticus. Found 

 in bad flour. DeGeer, Mem. vii. p. 97, pi. 

 15. fig. 15. (Ac.feculce, found by myriads 

 in potatoes. Guerin-Meneville, Ann. N. 

 Hist. 1867, xix. p. 71.) 



Rhizoylyphus (Claparede). Tarsi with 

 claws, but no suckers. Vegetable feeders. 



R. echinopus. In the bulbs of hyacinths. 

 Murray, p. 257, fig. ; Megnin, p. 144, fig. 

 49. 



R. phylloxera. On vine-roots. Murray, 

 p. 258. 



R. Robinii. On potatoes, dahlia, and 

 hyacinths. Murray, p. 259. 



R. rostroserratus. On decaying mush- 

 rooms. Murray, p. 260. 



Serrator (Megnin). Mandibles strongly 

 serrate ; a hook, but no caruncle. 



S. amphibius. In decomposing mush- 

 rooms. Megnin, p. 144, fig. 50. 



Ac. Dysenteric. Nyander, Amcenit. Acad. 

 v. p. 97 ; Linn. Grnel. p. 2929. Found in 

 the dejections of dysentery; also in old 

 casks. 



Ac. passerinus. Found upon young 

 birds. DeGeer, vol. vii. 139. Ac. chelopus, 

 Herm. Mem. Apteral, p. 82, pi. 3. fig. 7. 



Ac. (Carpoglyphus) passularum. With 

 two very long buccal bristles; lives upon 



dried figs, and other saccharine fruits. 

 He ring, Nova Acta, xviii. p. 618, pi. 45. f . 14, 

 15 ; Megnin, p. 141. 



Glyciphayus (Hering). Body soft, not 

 divided into two parts by a transverse line 

 or furrow, but with a dorsal depression, 

 and an anal projection ; legs perfect, with 

 acetabula ; hairs feathery. 



A. (Gl.) prunorum. Found on dried 

 plums ; produces the grocer's itch. Hering, 

 Nova Acta, xviii. p. 619. pi. 45. f. 16, 17 ; 

 Murray, p. 278, fig. 



A. (Gl.) hippopodos. Body as broad as 

 long, very acute anteriorly, entirely covered 

 with short hairs j a minute projection at 

 the end of the abdomen. On ulcers of 

 horses' feet. Hering, Nov. Act. xviii. p. 607 ; 

 Murray, p. 279, fig. An undescribed 

 Acarus has also been mentioned as occurring 

 upon the feet of sheep affected with the 

 canker. Grognier, Zool. veter. p. 233. 



A. (Gl.) hericius. Found on weeping 

 ulcers of elms. Robin, Journ. d. VAnat. 

 1868, p. 603. 



A. (Gl.) cursor. Found in the feathers 

 of the owl and in the cavities of the bones 

 of skeletons. The hairs are jointed. Ger- 

 vais, Ann. Sc. Nat. 2 ser. xv. p. 18, pi. 2. 

 f. 5 a ; Murray, p. 278, fig. 



A. (Gl.) spinipes. Like G. cursor, but 

 smaller ; the anal appendage short. Frem. 

 & Rob. Jn. Anat. 1867 ; Murray, p. 281, 



% 



A. (Gl.) balcenamm. On whales. Murray, 

 p. 282, fig. 



G. plmniger. With strongly feathery 

 hairs. In cellar-dust, stables, &c. Murray, 

 p. 283, fig. A beautiful object. 



G. palmifer. Smaller than the cheese 

 mite ; hairs leaf-like ; body granular. 

 Murray, p. 284, figs. Found with the 

 last. 



A. (Gl.} (Sar copies) palwnbinus. On the 

 pigeon. Koch, I. c. fasc. 5. pi. 12 ; Robert- 

 son, Qu. Micr. Jn. 1866, p. 201. 



Some other species have been insuffici- 

 ently examined : 



Ac. avicularum, DeGeer, Mem. vii. 106. 

 pi. 6. fig. 9. Louse of the grouse. Lyonet, 

 Mem. Mus. xviii. 281. pi. 15. f. 16. 



Ac. marilce, Gervais, Diet. Sc. Nat. Suppl. 

 i. 45. 



Ac.favorum. Found in old honeycombs. 

 Herm. Mem. Apterol. p. 86. 



Ac. fungi, Herm. /. c. 



Myobia (Heyden). Body elongate, rnauy- 

 lobed ; rostrum styliform. 



M. musculinus, Schranck, p. 501, pi. 1. 



