ISOPODS OF IVORTH AMERICA. 



159 



ALCIRONA HIRSUTA Moore. 



Alcirona hirsuta Moohe, Bull. U. S. Kinii Uoiniii., XX, I't. 2, 1902, j>. 170, pi. i.\, 

 figs. 6-10. 



Local iiy. — Off St. Thomas. 



I)i:pth.~1^-1?) fathoms. 



Found in coral bottom. 



""Front slightly pi'oducod and somewhat inHexed hotwoen the bases 

 of the antennules, not joining; the opistome: eyes small, lateral, dis- 

 tance between two or three times their diameter. Bod}' strongly 

 arched antero-postei-ioi-ly. Kpistome narrow, pentagonal. First 

 antenna' Avith two-jointed })e(liiiicl<' reaciiing to about end of fourtli 



Fig. 139.— Alcirona keebsii (After Hansen), a, Maxillipeu. 6, First maxilla, o, Distal 



PART OF MANDIBLE. d, DORSAL VIEW OF FEMALE. g, LEFT PLEOPOD OF SECOND PAIR IN YOUNG 



MALE. /, Lateral view of female, g. Leg of fifth pair, h. Leg of seventh pair, x, Man- 

 dible, j. Distal part of mandible, k. Second maxilla. I, Distal part of mandible. »;, Left 



PLEOPOD OF second PAIR IN ADULT MALE. ?i, LEG OF SECOND PAIR. O, POSTERIOR PART OF ABDO- 

 MEN (ADULT MALE), p, ANTERIOR PART OF HEAD FROM BELOW. 



joint of antennal peduncle. Flagellum slightly shorter than i)edun('le. 

 of seven joints, first joint as long as second and third. Second antenna' 

 reaching to middle of third segment, with tive-jointed peduncle; lirst 

 three joints short, fourth and tifth joints each about twice as long as 

 third and subecjual, ffagellum with seventeen joints. Mandibular palp 

 rather robust, three-jointed, second joint longest, second and third 

 joints with seta'. 



'']\Iaxillipeds with five-jointed rather robust palps. 



•■ First segment of trunk about 1.6 times as long as second, the next 

 five equal, the seventh a little shorter; third segment with a few setae 

 on lateral portion of posterior margin; fourth, fifth, sixth, and seventh 



