400 Mr. J. Blackwall on the Structure, Functions, (Economy, 



eminent arachnologist, would liave taken precedence of all others 

 had it not been previously employed by Fabvicius. 



Family Salticidce. 

 Genus Eresus, Walck. 



19. Eresus cinnaharinus. 



EresJis cinnaharimis, Walck. Hist. Nat. des Insect. Apt. t. i. p. 39.5 ; 



Latr. Gen. Crust, et Insect, torn. i. p. 121 ; Koch, Die Arachn. 



B. iv. p. lOG. tab. 138. fig. 318. 

 quadrigvttatus, Hahn, Die Arachn. B. i. p. 45. tab. 12. fig. 35 ; 



Koch, Die Arachn. B. iv. p. 104. tab. 138. fig. 31G ; Uebers. 



des Arachn. Syst. erstes Heft, p. 35. 

 ammlatus, Hahn, Die Arachn. B. i. p. 47- tab. 12. fig. 3C ; 



Koch, Die Arachn. B. xiii. p. 14. tab. 435. fig. 1087. 

 illustris, Koch, Die Arachn. B. iv. p. 105. tab. 138. fig. 317. 



I give this species, the only one of the genus hitherto found 

 in Great Britain, on the authority of Dr. Leach. See the Sup- 

 plement to the 4th, 5th and 6th editions of the ' Encycloptedia 

 Britanuica/ article Annulosa. 



Genus Salticus^ Latr. 



20. Salticus scenicus. 



Saliicus scenicus, Latr. Gen. Crust, et Insect, torn. i. p. 123 ; Hahn, 



Die Arachn. B. i. p. 57. tab. 15. fig. 43, 44. 

 Attus scenicus, Walck. Hist. Nat. des Insect. Apt. t. i. p. 406 ; Sand. 



Yet. Acad. Handl. 1832, p. 202. 

 Calliethera scenica, Koch, Uebers. des Arachn. Syst. erstes Heft, 



p. 31 ; Die Arachn. B. xiii. p. 37. tab. 439. fig. 1106, 1107. 

 —— histrionica, Koch, Uebers. des Arachn. Svst. erstes Heft, p. 31 ; 



Die Arachn. B. xiii. p. 42. tab. 439. fig. 'l 110, 1111. 

 Titulus 31, Lister, Hist. Animal. Angl. De Aran. p. 87. tab. 1. fig. 31. 



When searching on walls or the trunks of trees for those 

 insects which constitute its food, this common spider employs 

 much art, moving with great circumspection, and occasionally 

 elevating the cephalo-thorax, by straightening the anterior legs, 

 for the purpose of extending its sphere of vision. It runs with- 

 out diflBculty on the perpendicular surfaces of diy polished bodies, 

 having, like the other species of the genus, a small clinabing ap- 

 paratus situated below the tarsal claws, which, by the emission 

 of an adhesive secretion, gives it a secure hold upon objects. It 

 takes its victims by surprise, leaping suddenly upon them, and 

 by that act draws from the spinners a line attached by its extre- 

 mity to the station whence it took its spring, a necessary pre- 



