No. 2303. 



RED SPIDERS OP AMERICA— McOREGOR. 



665 



and the antepenultimate claw. Mandibular plate with subparallel 

 sides and subtruncate at front but unemarginated. Legs of moderate 

 length; foreleg, 0.33 mm.; femur I, two and one-half times as long 

 as broad; tibia I somewhat longer than patella I; tarsus in length 

 equaling tibia and patella together; the tarsal appendages, consist- 

 ing of the usual series of four tenent hairs and an empodial claw, 

 which is very sharply bent at middle at which point arises dorsally 

 a strong spur and ventrally a stronger division that immediately 

 splits into six * equal, slender, distally-curving, spine-hke claws 

 which considerably exceed in length the dorsal claw. Relative 

 lengths of the leg joints are as follows: Tro- 

 chanter, 10; femur, 25; patella, IS; tibia, 19; 

 tarsus, 37. There is but a single eye cornea 

 on each side, which is set in a shallow sub- 

 marginal socket directly over coxa II. Col- 

 lar trachea scythe-shaped, the anterior arm 

 running downward and backward with a 

 shght upward convexity near its middle and 

 then bending very sharply upward to form 

 the nearly straiglit posterior arm, which is 

 of similar cahber to the anterior arm. 

 The spur on the male palpus consists of a 

 spine-hke appendage set in a thuml)-like 

 prominence of the second joint. 



Type.— Cat. No. 19087, U.S.N.M. 



From Orlando, Florida, on castor bean 

 (Ricinus cormnurvls). This species is rather 

 close to the preceding species, but is proba- 

 bly distinct through the following characters: 

 Breadth of body; relative length of frontal to subfrontal bristles; 

 mandibular plate; proportions of terminal "finger." A more care- 

 ful study of tumidus material may eventually show that the species is 

 identical with quinquenychus. 



Genus PARATETRANYCHUS Zacher. 



Paratetranychtts Zacher, 1910, Mitth. Kais. Biol. Anst. f. Land u. Forst., Heft 9, 

 Januar, pp. 37-41. 



This genus contains at the present date two European species, one 

 South American species, and seven North American species. 



Red spiders, with empodial claw complex, appendiculate at base 

 or at point between it and middle point with from 4 to 8 spurs; dorsal 

 spur more prominent and much longer or at least equahng the 

 appendiculate spurs; collar trachea straight, enlarged at end into a 

 bladder-shaped chamber. 



> In the original description the author erroneously writes that the ventral claw division splits into 

 our spurs. We take this opportunity of correcting this statement as above recorded in the text. 



Fig. e.— Septanychus quinque- 

 nychus McGregor. 1, TARSAL 

 appendages; 2, collar tra- 

 chea; 3, palpal "thumb" AND 

 ITS appenpagk.s -(original). 



