TRACHEARI^ 323 



tremity; four eyes; the posterior legs longest; sucker projecting in 

 the form of a conical or subulate rostrum. Found under stones, 

 bark of trees, and in moss. 



Bd. longicornis; Acarus lon<jicornis,L.; La Pince rouge. 

 Geoff. ; Scirus vulgaris, Herm., Mem. Apter., Ill, 9 ; IX, S. 

 Hardly half a line in length ; scarlet ; the feet paler ; sucker in 

 the form of an elongated and pointed rostrum ; quadriarticu- 

 lated palpi, the first and last joint of which are the longest ; the 

 latter somewhat the shortest of the two, and terminated by two 

 setae. Common in the environs of Paris ; under stones *. 



Smaridia, Lat. 



Distinguished from Bdella by the palpi, which are hardly longer 

 than the sucker, straight and without terminal setae ; by the eight 

 eyes, and by the two anterior legs, which are longer than the others f. 



Sometimes these Ticks, with eight legs and without chelicerse, 

 have no eyes that are perceptible ; their palpi are either anterior and 

 projecting, but in the form of valvulae, widened or dilated near the 

 extremity, serving as a sheath to the sucker — or inferior; the parts 

 composing the sucker are horny, very hard and dentated ; the body 

 is invested with a coriaceous skin, or has at least, anteriorly, a scaly 

 plate. 



These animals are parasitical, gorge themselves with the blood 

 of several of the Vertebra ta, and from being extremely flat, acquire 

 by suction a great volume and a vesicular form. They are round 

 or oval. 



Ixodes, Lat. Fab. — Ctnor h.estes, iJerm. 



The palpi forming a sheath to the sucker, and with it constituting 

 a projecting and short rostrum, truncated and slightly dilated at the 

 extremity. 



The Ixodes are found in thick woods abounding in bushes, briars, 

 &c. ; they hook themselves to low plants by the hind legs, keejHng 

 the others extended, and fasten on Dogs, Oxen, Horses, and other 

 Quadrupeds, and even on the Tortoise, burying their sucker so com- 

 pletely in their flesh, that they can only be detached by force, and by 

 tearing out the portion that adheres to it, They lay a prodigious 

 quantity of eggs, which, according to M. Chabrier, are protruded 

 from their mouth. They sometimes increase to such an enormous 

 extent on the Ox and Horse, that they perish from the exhaustion. 

 Their tarsi are terminated by two hooks inserted in a palette, or 

 united at base on a common pedicle. 



The ancients designated these Arachnides by the term Ricinus. 



* Scirus longirostris, Herm., Mem. Apter. VI, 2; — S. laiirostris, lb., II, III; — 

 S. setirostris, lb., Ill, 12; IX, T. 



f Acarus sambuci, Schrank, and perhaps the following Trombidia of Hermann ; 

 Tr. miniatum, 1, 7; — Tr. papillosum, II, 6; — Tr. squainmatum , lb., 7. The second 

 is even closely allied to the species which serves as a type to the genus. 



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