1904.] NATURAL SCIENCES OF PHILADELPHIA. 49 



lateral borders emarginate, apex rectangulate. Limbs rather short; all 

 lobato to a greater or lesser extent. Anterior femora three times the 

 length of the pronotum, basal flexure occup^ang almost half the entire 

 femur, superior margin with an apical dentate foliaceous lobe; tibiae 

 about equal to the femora in length, superior margin with four rounded 

 lobes, decreasing in size toward the apex; metatarsi short, exceeded in 

 length by the terminal tarsal joint and about equal to the second and 

 third together. Median femora about equal to the anterior femora in 

 length, posterior superior margin with a large bidentate apical lobe and 

 several smaller ones distributed between the large one and the proximal 

 extremity, anterior superior margin wdth several low rounded lobules, 

 inferior margins with several low lobules and a median bidentate apical 

 lobe; tibiae about equal to the femora in length, the superior margin 

 with three lobules decreasing in size toward the apex ; metatarsi as in 

 the anterior limbs. Posterior femora equal to the four basal joints of 

 the abdomen in length, the superior margin with three large subpyrami- 

 dal lobes, the largest being bilobate and placed at the distal extremity, 

 several small lobules are located between the larger lobes, inferior 

 margins with several small low^ lobules, the apical larger than any of the 

 others and strongly bilobate; posterior tibiae exceeding the femora 

 by half the length of the fifth abdominal segment, superior surface 

 with three rounded lobules, decreasing in size toward the distal 

 extremity; metatarsi as in the anterior limbs. 



General color brownish-black, becoming reddish-brown toward the 

 apex of the abdomen ; antennae with the three terminal segments pale 

 ochraceous. 



Mcasiirouenfs. 



Total length, 78 mm. 



Length of pronotum, 5.5 '' 



Length of mesonotum, 22 " 



Length of metanotum (including median segment), . . . 9.5 '" 



Length of median segment L9 '" 



Length of abdomen 39 '" 



Length of anterior femora, 14.8" 



T>ength of anterior tibiae, 15.5 '" 



Length of median femora 12.5 '" 



Length of posterior femora, 16 



There is a small female specimen from Tueurrique, Costa Rica, in 



the U. S. National ]\Iuseum collection, Avhich resembles very much 



the type of bigibbus. A number of points of difference, however, exist. 



but as these conditions in the specimen may be due to immaturity. I 



4 



