NO. 6 ANNELIDA, ONYCHOPHORA, AND ARTHROPODA SNODGRASS I23 



Vs Sty 



Fig. 52. — Symphyla, Diplopoda, and Thysanura. 



A, Scutigerella itnmaciilata Newport (Symphyla). B, same, maxilla. C, 

 same, labium. D, labium of Machilis sp. (Thysanura). E, mandible of 

 Scutigerella. F, mandible of Machilis. G, gnathochilarium of Fontaria vir- 

 giniana (Drury) (Diplopoda). H, thirteenth body segment of Scutigerella, 

 ventral view. I, seventh abdominal segment of Machilis, ventral view. J. thir- 

 teenth body segment of Scutigerella, lateral view. K, last leg of Scutigerella, 

 posterior view. L, terminal segments of Scutigerella, lateral view. 



a, a", a'", cranial articulations of mandible, maxilla, and labium; Cd, cardo; 

 Cer, cercus ; Cx, coxa; dac, dactyl (clawlike remnant of dactylopodite) ; flee, 

 cranial flexor muscle of lacinia ; Fm, femur ; Ga, galea^ H, head ; Lc, lacinia ; 

 Pip, palpus ; Ptar, pretarsus ; St, stipes ; Stn, sternum ; Sty, stylus ; Tar, tarsus ; 

 Tb, tibia; Tel, telson; iTr, first trochanter; 2Tr, second trochanter (prefemur) ; 

 un, lateral claw (unguis) of pretarsus ; Vs, eversible vesicle; 1-16, body segments. 



