THE MYRIAPODA OF NORTH AMERICA. 63 



body. Male: Mandibulary stipes a little produced in the middle; gen- 

 italia concealed. Length of body 18""", width — mm . 

 Habitat. — Utah ; California. 



I have examined two adults and two young of this species collected 

 by Mr. James K. Burke, after whom the species is named. 



Genus II. — Parajulus, Humbt. and Sauss. 



To this genus belong our larger species of so-called Julus. Prom the 

 latter genus it is easily separated by the number of mandibulary combs 

 (10), the dwarfed second pair of feet and the form of the first seg- 

 ment of the male with its appendages. 



Under the genus Julus, Wood says, "In all species in which I have 

 had the opportunity of examining sexes, the form of the first scutum 

 distinguishes them with certainty. In the male its anteroposterior 

 diameter is large, and there are well marked lateral margins running 

 nearly at right angles to the others. In the female the anterior pos- 

 terior diameter is much less, but laterally the scutum is so produced 

 that the anterior and posterior margins may in most cases be said to 

 meet one another at an angle. The males are further distinguished by 

 a peculiar alteration of the first pair of feet, which are transformed into 

 a pair of very large, thick organs." 



By applying this remark to those species of which he had both sexes, 

 we have most of the species known to be in this genus at present. The 

 following is a key to the subgenera: 



a. First segment enlarged in the male. First pair of feet of male large, crassate, 

 numerous snort tubercles on the inner side Para.juus 



aa. First segment alike in both sexes. First pair of feet of male short, thick, tuber- 

 cles absent Pseudojulis 



Sub-genus Parajulus. 



2. Parajulus castaneu3, sp nov. 



Color nearly the same as in P. impressus (Say). Moderately slender, 

 rough, not pilose. Vertex finely wrinkled, a faint median sulcus, se- 

 tigerous foveolse present. Antennae equaling the width of body. Eyes 

 distinct, triangular, ocelli 54-8. Segments, 42-51. Sides of first seg- 

 ment striated, others deeply striate beneath, above with numerous short 

 lines, which are branched. Last segment produced into a moderate 

 spine, projecting beyond the anal valves, not pilose; anal valves not 

 marginate, pilose; anal scale obtusely rounded, small. Repugnatorial 

 pore moderate, touching the transverse suture, which is sharply sinuate. 

 Pairs of feet GO, equaling the width of body. Male: Mandibulary 

 stipes strongly produced ; coxa 1 of the second pair of feet as in impress us; 

 genitalia about half concealed, composed of three plates; anterior plate 

 round, clavate, pilose; middle plate curving up in front of anterior, 

 and expanding between them into an elongate plate, which has three 



