REPORT ON THE COPEPODA. 117 



Copilia mirabilis, Dana (PL LIII. figs. 1-11). 



Copilia mirdbilis, Dana, Crust. U. S. Expl. Exped. (1852), p. 1232, pi. lxxx. fig. 14, a-g. 

 „ dentici.ila.ta (?), Claus, Die frei lebenden Copepoden, p. 161, pi. xxv. figs. 14-20. 



Length, 15-100ths of an inch (3*6 mm.). The first cephalothoracic segment is quad- 

 rangular, much broader than, and as long as, the rest of the body, exclusive of the caudal 

 stylets ; the last two thoracic segments are much smaller than the rest and are 

 prolonged on the dorsal aspect into a triangular median spine, and the posterior borders 

 of the abdominal segments are denticulated; the last abdominal segment is as long as the 

 preceding five, and somewhat dilated at the distal extremity; the caudal stylets excessively 

 long and slender, almost linear, divergent, about half as long as the body of the animal, 

 and bearing a few very short terminal setse. Anterior antennas (fig. 3) six-jointed, 

 small, rather sparingly setiferous, and reaching only about half-way to the posterior 

 margin of the first body-segment. Posterior antennae (figs. 4, 5) very large, reaching to 

 the hinder extremity of the first segment, four-jointed, and terminating in a strong, 

 curved claw, second and third joints each bearing a strong marginal spine ; in some 

 examples (? males) this spine is branched in a radiate manner near the base (fig. 5). The 

 swimming feet (fig. 10) are short, the external and internal branches of the first four pairs 

 being three-jointed and equal in length ; marginal spines of the external branches 

 obsolete; inner branch of the fourth pair (fig. 11) consisting of one joint only; fifth 

 pair of feet wanting (?), or rudimentary. 



Habitat. — This species occurred very sparingly in several gatherings ; except in one 

 instance not more than two or three examples were noticed in the material which passed 

 through my hands from any one locality. The following list includes all the gatherings 

 in which the species occurred : — Off Sibago Island, and in several other gatherings from 

 amongst the Philippine Islands ; off the north coast of Papua ; off Kandavu, Fiji ; 

 between Api and Cape York ; near the Ki Islands (Station 181); Zamboanga ; 

 in lat. 9° 43' S., long. 13° 51' W. (Station 342) ; in lat. 5 C 28' N., long. 14° 38' W. 

 (Station 349) ; and in lat. 10° 55' N., long. 17° 46' W. (Station 352). It will be seen 

 from this list that all the localities in which Copilia was captured may be assigned to two 

 widely distant areas, the most important area including Polynesia and the Malay Archi- 

 pelago ; the other the North Atlantic, off the west of Africa. I have not been able to 

 detect any important differences amongst the specimens taken from the various places, but 

 the action of the preservative spirit has in all cases so destroyed or obscured the more 

 delicate internal structures, that I have been obliged to rely upon the observations of 

 previous writers for descriptions of those parts. In other respects, many of the specimens 

 were in good condition, except as to the setse of the caudal stylets, none of which appear 

 to be perfect. The mouth-organs are extremely minute, and — in spirit-specimens at any 

 rate — difficult of observation, and I am by no means sure that my drawings of those parts 



