10 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.65. 



{tro^ fig. 33) is approximately one-third the length of the coxa and 

 articulates to the coxa at its proximal end by a pair of condyles. 

 The ventral surface of the trochanter is much longer than its dorsal 

 surface. The femur {fe, fig. 33) is attached to the dorsal surface 

 at the distal end of the trochanter. It is about twice as long as 

 the trochanter and is slightly larger at its distal end. The tibia 

 (ti, fig. 33) is short, cylindrical, and attached obliquely to the distal 

 end of the femur. The tarsus (ta, fig. 33) is still shorter and bears 

 at its distal end two curved claws. Both claws are movable by 

 muscles. The cephalic claw is about one-half longer than the caudal 

 one. The setae on the segments of the legs are arranged as shown 

 in figure 33. 



ABDOMEN. 



The abdomen (fig. 1) is ten-segmented, subcylindrical, and grad- 

 ually increases in size to the fifth segment, from which one it grad- 

 ually decreases to the caudal segment. All of the segments are quite 

 similar except the fifth and the last three. The tergum, pleurum. 

 and sternum are easily distinguished, and a description of one seg- 

 ment will suffice for all except the fifth and the last three. The 

 third abdominal segment is the one chosen for this description. The 

 segment consists principally of membrane, but has a number of dis- 

 tinct chitinized areas. 



The tergum {te, fig. 96) has a pair of suboval sclerites, one on each 

 side of the meson. These sclerites bear four or five long, prominent 

 setae and several smaller ones. 



The pleurum consists of two distinct regions, the epipleurum and 

 hypopleuiiim, separated from each other by the indistinct i^entro- 

 lateral suture. The epipleurum {epl., fig. 96) has a single large, 

 chitinized sclerite with several setae, and usually three small, chi- 

 tinized spots carrying a single seta. The kypopleurum {hy., fig. 96) 

 also contains a single large, oval sclerite with a number of setae, and 

 three small chitinized spots bearing a single seta. 



The sternum, consists of several chitinized areas, namely, the 

 eusternum, sternellum (=:intersternellum, Lengerken), and coxal 

 lobes (=extrasternellum, Lengerken). The eusteimum {eust., fig. 96) 

 is the single large sclerite on the cephalo-mesal part. It bears four 

 pair of setae. There are three small chitinized spots, bearing a 

 single seta, cephalo-laterad of the eusternum. The sfermellum 

 {stl, fig. 96) consists of a pair of oval sclerites, one on each 

 side of the meson, caudad of the eusternum. These sclerites bear 

 four or five setae. The large, suboval sclerites laterad of the ster- 

 nellum are the coxal lobes (cxl, fig. 96). They bear four or five 

 prominent setae and several smaller ones. The number and arrange- 

 ment of the setae on the sesfment are shown in figure 96. 



