202 ARACHNIDES. TRACHEARI*. 



formed for leaping, the fourth pair longest, then the first; the 

 third pair shortest; eyes disposed in two quadrangles, one in- 

 closed within the other. 



E. moniligerus, Leacli. (E. cinnaberinus, Lat.) Black ; abdomen 

 above vermilion, with four or six black dots, arranged in two 

 longitudinal lines ; joints of the legs whitish ; sides of the thorax 

 and thighs pale vermilion. Inhabits France, Germany, and Eng- 

 landI**. Gen. i. 121. 



Gen. 31. SALTICUS, Lat. Aranea, Lin. 

 Maxillae straight, longitudinal, subrhomboidal; lip elongate, sub- 

 oval, the apex obtuse ; eyes disposed in the form of a horse- 

 shoe, the two middle ones largest ; legs thick and short, the 

 first pair thickest, the fourth longest. 



S. scenicus, Lat. Black ; margin of the thorax covered with white 

 down; abdomen short ovate, with a reddish gray pubescence above, 

 and three transverse bent lines, the anus white. Inhabits walls 

 and palings in Europe. In Britain it is called the Hunting- 

 spider. Lat. Gen. i. 123. 



ORDER II. TRACHEARI.E. 



A single dorsal vessel in place of a heart ; respiration effected 

 by radiated tracheae, generally receiving the air by abdomi- 

 nal or thoracic spiracles ; sexual organs single; eyes never be- 

 yond four, generally but two, and wanting in some ; mouth 

 in the greater number in form of a syphon. 



FAMILY T. PYCNOGONIDES. 



Syphon tubular, projecting ; four eyes on one tubercle; feet often 

 very long, terminated by unequal hooks ; two oviferous feet 

 at the base of the first. 



The animals of this family have a linear body, articulated in all its length, with 

 very long legs, of eight or nine joints, terminated by unequal hooks. The first 



didactyle, with the inferior or immoveable toe sometimes shortest. The palpi are 

 also filiform, of five joints, with a hook at the end. Each segment of the body, with 

 the exception of the first, carries a pair of feet ; the first segment having above and 

 on each side two smooth eyes, and below in the females two small feet for carrying 

 the ova ; the last segment is small and cylindrical. 



Gen. 1. NYMPHON, Lat. 



Mandibles longer than the rostrum, with equal joints, the fin- 

 gers curved, meeting along their whole length, and abruptly 

 hooked at their extremities; palpi six-jointed, the second joint 

 elongate, the sixth very small; legs very slender, claws simple; 

 egg-bearing organs ten-jointed, inserted behind the rostrum. 



