I9OPODS OF NORTH AMERICA. 



669 



the .second; the fourth is equal in length to the second; the fifth is 

 twice as long as the fourth. The flagelluin is composed of two long, 

 subequal articles. The second antenna 1 extend to the posterior margin 

 of the first thoracic segment. 



The first segment of the thorax is a little longer than any of the 

 following segments, and has the 

 antero-lateral angles produced 

 forward to surround the head, 

 and the post-lateral angles pro- 

 duced backward. The epimera 

 are not distinct in any of the 

 segments. 



The first two segments of the 

 abdomen have the lateral parts 

 covered by the seventh thoracic 

 Hegment. The three following 

 segments continue the oval out- 

 line of the body. The sixth or 

 terminal segment is sub-triangu- 

 lar. with sides a little concave 

 and apex rounded. The basal 6 



segment Ol' peduncle of the Uro- FIG - ^OX.-ARMADILLIDIUM QUADRIFRONS. a, HEAD. 

 . ., , . x 14J. b, LAST TWO SEGMENTS OF ABDOMEN WITH 



poda is not visible in a dorsal UKOPODA. x m. 

 view. It is large and somewhat 



quadrate. The outer branch occupies all the space between the lateral 

 part of the fifth abdominal segment and the terminal abdominal seg- 

 ment. The outer branch is broad posteriorly and well rounded. The 

 inner branch extends to the extremity of the outer branch and to 

 the extremity of the abdomen. 



All the legs are ambulatory in character. 



121. Genus UROPODIAS Richardson. 



Head with the front produced in a prominent rounded lobe. Eyes 

 small, obscure. External antenna 1 , with a flagelluin of two joints, the 

 second joint the smaller of the two. 



First six thoracic segments with the lateral parts lamellarly expanded. 

 Seventh segment as long as the six preceding segments, but with the 

 lateral parts undeveloped, and not wider than the first two abdominal 

 segments, which likewise have the lateral parts or epimeral plates 

 undeveloped. 



Abdomen not narrower than the thorax, the lateral parts of the 

 third, fourth, and fifth segments being expanded and continuing 

 the regular outline of the body. The abdominal segments equal in 

 length and half as long as the thoracic segments. Terminal segment 

 quadrangular in shape, the posterior margin produced in a medium 



