ARTICUr.ATA. 643 



CLASS Ml.— ARACHNIDES. 



For the characters of this class, see vol. iv. page 203. Lamarck divides it 

 iuto three orders. 



ORDER I. PULMONARI^. 



Provided wth a heart, or organ of circulation; branchial sacs placed on 

 each side of the abdomen below ; the sexual organs are double ; with from 

 six to eight smooth eyes ; they are furnished with two pedipalpi, with one 

 or two toes at their termination, one of which is always moveable ; two 

 jaws, and palpi, and four pairs of feet. This order contains thirty-one 

 genera. 



Scorpio Eurnpcetis.—The European Scorpion. Plate Ixvi. fig. 1. Described, 

 vol. iv. page 233. 



Thelyphonus proscorpio. — The Tarantula. Plate Ixvi. fig. 2. Described, 

 vol. iv. page 217. 



MygaJe avicularia.— The Bird-Catching Mygale. Plate Ixvi. fig. 3. De- 

 scribed, vol. iv. page 216. 



Argyroneta aquatica.— The Aquatic Spider. Plate Ixvi. fig. i. Described, 

 vol. iv. page 207. 



Scytodes Oioracica.— The Thoratic Scytodes. Plate Ixvi. fig. 5. Skiu 

 coloured, spotted with black ; with a large orbicular thorax, produced and 

 rounded behind; abdomen nearly white and subglobose. Inhabits houses at 

 Paris. 



Epeira d i ad e ma. —The Crown Epeira. Plate Ixvi. fig. 6. Abdomen 

 nearly ovate and globose, with an elevated ridge on each side of its base ; 

 of a reddish chestnut-brown colour, and spotted with yellowish-white. 

 Inhabits Europe, in woods and gardens. 



Lycosa tarentula.— The Tarentula Lycosa. Plate Ixvi. fig. 7. Brown ; 

 back of the abdomen with a row of trigonal black spots, white on the edges ; 

 legs having black and white bars. Inhabits Southern Europe. 



Salticus scenicus.— The Scenicus Salticus. Plate Ixvi. fig. 8. Black ; 

 margins of the chest covered with white down. Inhabits old walls of Europe. 



ORDER II. TRACHEARI^. 



Instead of a heart provided with a single dorsal vessel, they perspire by 

 radiated tracheae, and receive the air by spiracles placed in the abdomen or 

 thorax ; sexual organs single ; eyes usually two, but never exceeding four, 

 and some species are devoid of them ; most species have a syphon.shaped 

 mouth. The order embraces twenty-seven genera. 



PhoxichUus hirsutus.— The Hairy Phoxichilus. Plate lx\i. fig. 9. The 

 articulations of all the joints of the limbs provided with hairs. 



Obisium Trombidoides.— The Troniboidal Obisium. Plate Ixvi. fig. 10. 

 The second joint of the arms considerably elongated ; fingers long and 

 etraight; dark brown, and covered with ciliated hairs. Inhabits England 

 and France, under stones. 



Phalanginm cornutum.— The Horned Phalangium. Plate Ixvi. fig. 11. 

 Reddish ash-coloured above ; the mandibles and antennae whitish. Inhabits 

 Europe, in walls, &c. 



Acarus domesticiu.--The Cheese Mite. Plate Lxvii. fig. 1. Body ovate. 



