202 



BULLETIN 54, UNITED STATES NATIONAL MT^SEUM. 



large, oval, eomposito, separated in front by a distance nearly equal 

 to the width of one ey e. Basal article of the first pa'ir of antenna? 

 short and nearly concealed l)y the front of the head; second article 

 twice as long- as the basal article; third ailicle twice as long- as the 

 second one. Flagelluni is composed of six articles. The tirst antennae 

 extend to the end of the peduncle of the second pair of antenna^ or to 

 th(^ antei-o-lateral angle of tho tirst thoracic segment. The tirst two 



articles of the second pair of antennae 

 " * are short, the second shorter than the 



tirst; the third is twice as long as the 

 tirst; the fourth is equal in length to 

 the third; the tifth is one and a half 

 times longer than the fourth. The 

 tlagellum is composed of fourteen to 

 fifteen articles. The second antennae 

 extend to the posterior margin of the 

 second thoracic segment. The frontal 

 lamina is small, almost inconspicuous, 

 rhomboid-shaped at the base, Avhich is 

 ventrally placed. The maxilliped has 

 a palp of two articles. 



The first segment of the thorax is a 

 little longer than the others. The 

 epimera are distinct from the seg- 

 ments in all but the first segment; 

 the}"^ are narrow plates with the pos- 

 terior extremity very acute in the last 

 four. The epimeron of the seventh 

 segment is produced l)e3'ond the pos- 

 terior margin of the segment. A 

 distinct carina ()bli([uely crosses all 

 the epimera. 



The first segment of the al)domen 

 is almost entirely concealed l)y the 

 seventh thoracic s(>gnient. The lat- 

 harger). a, Dorsal vikw of female, g^.^j parts of the alidouiinal segments 



X 2. 6, Ventral view of female, x 2. ^ . i -i- i- ii i 1 



c, Head and first thoracic segment of are not separated oft from the dorsal 

 male. x2. d, Leg of sixth pair. :.(^. portion. The sixth or terminal seg- 



fi, Leg of first pair. < (if. . , , ^ . , rni 



ment is rounded posteriorly. Itie 

 inner branch of the uropoda is longer than the outer branch and a 

 little wider. It does not extend beyond the extremity of the terminal 

 abdominal seguK^it. The peduncle extends as far as the tip of the 

 outer ])ranch. Both branches are rounded posteriorly, Uropoda and 

 terminal altdoniinal segment furnished with spines along the margins. 



Fig. 195.— Rocinela Americana (After 



