206 ARACHNIDES. TEACHEAHLE. 



C. eruditus, Lat. Whitish or brownish, very minute. Found in books, 

 (whence the specific name,) museums, c Lat. Gen. i. 153. 



Gen. 15. UROPODA, Lat. 



Organs of manducation concealed ; body covered with a scaly 

 skin ; feet very short ; anus produced into a long filiform pe- 

 duncle, by which it adheres to coleopterous insects. 



H. vegetans, Lat. Brown, very smooth, shining. Inhabits France 

 and England. Lat. Hist. viii. pi. 67, fig. 8. 



Gen. 16. ACARUS, Fab. Lat. 



Body very soft ; mouth naked ; palpi short or concealed ; tarsi 

 terminated with a vesicular ball. 



A. domesiicus, Lat. The Mite. White, with two brown spots ; bo- 

 dy ovate, the middle coarctate, with very long hairs ; legs equal. 



Inhabits houses, in cheese and flour that have been kept long 



Lat. Gen. i. 150. 



Gen. 17. ORIBATA, Lat. Acarus, Lin. 

 Body covered by a coriaceous skin ; anterior part rostrated, the 

 produced part inclosing the organs of manducation ; abdomen 

 subglobose ; tarsi with claws. 



O. geniculata, Lat. Fuscous chestnut-coloured, shining, hairy ; 

 legs pale fuscous ; thighs subclavate. Inhabits Europe, on trees 

 and under stones. B. Lat. Gen. i. 149. 



Gen. 18. EYLAIS, Lat. 



Mandibles depressed, armed at their joints with a claw ; palpi 

 elongate-conic, arcuate ; eyes four. 



E. extendens, Lat. Body rounded, shining, smooth, red, immacu- 

 late ; hinder legs short. Inhabits Europe in stagnant waters. 

 Lat. Gen. i. 158. 



FAMILY V. HYDRACHNELL.E. 



Feet proper for swimming. 



Gen. 19- HYDRACHNA, Mull. Lat. Trombidium, Fab. 

 Palpi subcylindrical, porrect, inflexed, with four joints, the last 

 acute ; mouth produced into a conical rostrum ; body glo- 

 bose ; legs fimbriated with hairs, and at equal distances. 



H. geographica, Mull. Body globular, with scarlet spots and dots. 

 Inhabits Europe, in waters that flow gently. B. Lat. Gen. i. 159. 



Gen. 20. LIMNOCHARES, Lat. Acarus, Lin. 

 Palpi incurved, the apex acute, simple ; mouth with a very 

 short rostrum ; body depressed ; legs short, the four hinder 

 ones remote ; eyes two. 



L. holosericeay Lat. (A. aquaticus, Lin.) Body ovate, red, rugose, 

 soft ; eyes black. Inhabits ponds in the summer months, vary- 

 ing much in colour. B Lat. Gen. i. 160. 



