52 BULLETIN 46, UNITED STATES NATIONAL MUSEUM. 



Young examples differ from the adults as follows : 



Length. 



m in. 

 25 

 27 

 24 

 22 



Width. 



Segments. 



Pairs of 

 feet. 



Ocelli. 



24-6 



25-0 

 15-5 

 19-0 



mm. 



2.5 



3. 



2.5 



2.3 



50 

 49 

 44 

 43 



80 

 81 

 65 

 70 



."ienus in — Parajulus Humbert and Saussure. 



Parajulus Humbert and Saussure, Revue et Mag. Zool., 155, 1869 (olmecus). 



Eyes triangular, elliptical or trapezoidal; ocelli numerous, not ar- 

 ranged in more than ten series. Antennae subfiliform, scarcely subela- 

 vate, second jointlongest. Mandibulary combs, 9-10. Gnathochilarium 

 scarcely subspatulate ; stipes not separated ; nientum bipartite, almost 

 hidden; lingual plate separated; lingual lobes denticulated. Number 

 of segments uncertain, 40-70 ; sides striate. Last segment more or less 

 produced into a spine; anal scale triangular or somewhat rounded. 

 Kepugnatorial pore beginning on the sixth segment, placed in the 

 posterior part. Third segment apodous. Feet equaling the width of 

 body, seventh joint longer than third; second pair of feet very strongly 

 stunted or dwarfed. Male: First pair of legs enlarged, six-jointed, the 

 fourth largest. 



To this genus have been referred our larger species of so-called Jidm; 

 from the latter genus it is easily separated by the number of man- 

 dibulary combs, by the second pair of legs, and the first jiair of the 

 male. 



This genus is divisible into the following subgenera: 



* Male : Promentum very large, ovate, narrowing the lingual plates ; first segment 

 enlarged, sides very broad, almost subquadrate; first pair of feet very large, 

 crassate, curving inwards and crossing each other, armed with numerous tuber- 



1 cles on the inner side, moderately pilose Parajulus i. 



** Promentum and first segment same size in both sexes; first pair of feet of male 

 small, stumpy, crassate and straight, tubercles absent, sparsely pilose. 



Pseudojumjs, subgen. nov. ir. 



Subgenus Parajulus. 



11. Parajulus impressus (Say). 



Julus impressus Say, Jour. Acad. Nat. Sci., Phila., 103, 1821. 

 Chestnut brown, the median line and a lateral row of spots black, also 

 an indistinct row of large dark spots partly covered by the feet ; seg- 

 ments above with two short light lines, and pale spots on each side of 

 the lateral line; feet pale; line between the eyes not. very dark. Mod- 

 erately slender, not pilose or smooth. Vertex with a median sulcus, 

 setigerous foveohe present. Antennae long and slender, equal to the 

 width of the body, moderately pilose. Eyes distinct, triangular, the 



