558 



BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



Fig. 608.— Pbobopy- 

 rus bithynis. leg 

 of sixth pair of 

 adult female. 



X 39. 



evident as narrow pieces lateral to the ovarian bosses on all the 

 segments. 



The segments of the abdomen are distinct on the dorsal side. The 

 lateral margins of the first live seg- 

 ments are straight. The sixth or 

 terminal segment is narrow, elon- 

 gate, and has a slight emargina- 

 tion in the middle of the posterior 

 margin. 



The pleopoda are five pairs of 

 double-branched appendages, the 

 inner branches of the first pair 

 being the largest and overlap- 

 ping in the middle ventral line. The uropoda are 

 wanting. 



The first pair of incu])atory lamellae are large 

 and extend about half the length of the ventral side 

 of the thorax. In fact all the lamelhe are quite 

 large, and encompass the marsupium, leaving 

 only a comparatively small opening into the pouch. 



All the legs have an extremely high expansion or carina on the 

 basis. 



The male has the thorax distincth^ segmented, the segments not 

 being widely separated at the sides. Body of male short and thickset, 

 being only twice as long as wide. 



The abdomen is a little more than one and a half times broader than 

 long. The segments of the abdomen are oidy indicated at the sides, 



Fig. 609.— Probopyrus 

 BITHYNIS. Male. 

 X 41. 



Fig. fiio.— Probopyri's KiTHVNi^;. a. Ixirsal view of female. 6, Ventral view of same, x 8. 



being fused in the middle of the dorsal surface; they gradually de- 

 crease in size to the sixth or last, which is a narrow piece situated 

 between the two lobes of the fifth segment and which does not reach 



