:130 MODERN SYSTEM. 



Aranea scenica. Linn., Fahr. Atte pare. IVakk. Salticus sccniciis. 

 Latr., Leach. 



Inhabits walls and palings. It is found in most parts of Europe, and is 

 called in Britain the Hunting Spider. 



Genus 23. ATTUS. Walck., Leac/i's Siipp. to Encycl. Brit'. Sal- 

 ticus. Latr., LcacliS Edin. Eiin/cl. vol. vii. 



Maxilla straight, longitudinal, subrhomboidal or inversely cuneate- 

 ovate : lip elongate, suboval, with the apex obtuse : palpi^ filiform : 

 thorax elongate, narrow, subconic : lyes disposed in the form of a 

 horse-shoe; the two middle eyes largest: %.s- slender, elongate, the 

 first pair thickest and not longer than the fourth pair ; the second 

 and third pairs of nearly an equal length and shorter than the other 

 pairs. 



Sp. 1. Att.formicariiis. Thorax anteriorly black, behind red : abdomen 

 fuscous, "with a white spot on each side : legs red. 



Attus formicarius. Walck. Salticus formicarius. Latr., Leach. Arai- 

 gnee fournii. De Geer. 



Inhabits Europe, residing on pla'nts and walls. It is very rare in Scot- 

 land, and has not been observed in England. 



Class IV. A CAR I. Leach's MSS. 



In the Supplement to Enci/cl. Brit. vol. i. the animals of this Class 

 were arran"-ed with the Arachnokla and formed the Order Monomero- 

 somata. Since that paper was written. Dr. Leach has, from a further 

 investio'ation of their characters, separated them from the Arachnoida 

 (in which they differ essentially), and considers them as a distinct 

 class ; they are for the most part parasitic, living on the bodies of 

 other animals : to the lovers of the microscope these animals will af- 

 ford an extensive field for their research and investigation; they are 

 very numerous, highly interesting, and as yet but imperfectly known. 



Character. — Bodi/ formed bul: of one segment : mouth rostriforni, 

 or m some furnished with maxilte and mandibles : legs si.\ or eight : 

 trachea for respiration. 



Section I. — Legs formed for toalking. 



A. Mouth with mandibles. 



Fam. I. Trombidiad.?:. Leach. 



Palpi porrect, and furnished at their extremities with a moveable ap- 

 pendage. Ei/cs t\vo, placed on a pillar. Body apparently divideci 

 into two parts by a transverse line; the antevior division bearing the 

 eyes, mouth, and four anterior legs. 



