REPORT ON THE COPEPODA. 103 



olfactory filament ; in the male (fig. 3) the antenna is geniculated, and has a slender claw- 

 like apical joint. The posterior antenna (fig. 5) is two-jointed and cylindrical, the first 

 joint having attached near the middle a minute one-jointed branch, which bears two stout 

 pectinated setse, the last joint about half as long as the first, and provided with four apical 

 setae of unequal length, and bearing also a small seta on the outer margin. Mouth- 

 organs extremely minute. Mandible simple, cylindrical (fig. 7), obscurely toothed at 

 the apex, and beset on one margin with a series of closely-set fine hairs. Maxilla (fig. 6) 

 short, quadrate, truncated, and strongly toothed at the apex, bearing a small simple palp, 

 which has a large marginal seta and three smaller apical ones. Anterior foot-jaw (fig. 8) 

 short and stout, divided into several (about four) stout marginal setiferous digits ; 

 posterior (fig. 9) elongated, narrow, two-jointed ; first joint bearing only a single small 

 marginal hair, second truncated and serrated at the apex, which is armed with a short and 

 stout hook-like claw ; the first joint about five times, the second three or four times, as 

 long as broad. The second, third, and fourth pairs of feet are nearly alike, and the same 

 in both sexes (except the second pair of the male), having both branches three-jointed 

 and of nearly equal length; the first pair is similar in male and female (fig. 10), and 

 differs from the rest in having the inner branch composed of only two joints, and in being 

 less profusely setose ; the inner branch, too, is slightly longer than the outer ; in the male 

 the inner branch of the second pair (fig. 11) is two-jointed, the last joint being composed 

 apparently of the coalescent second and third joints; fifth foot (figs. 13, 14) composed 

 of two foliaceous joints, not very dissimilar in the two sexes, the basal joint fringed with 

 four or five, the apical with six stout setse. The first abdominal segment in the female 

 is formed by the confluence of two somites, and shows a more or less distinct division into 

 two parts, in the male, the first segment has the postero-ventral angle produced 

 and setiferous (fig. 15); caudal stylets cylindrical, about thrice as long as broad; 

 terminal setse three, the longest being considerably shorter than the abdomen. The 

 ovisacs of the female contain only a small number of very large ova. 



Habitat.— -Lat. 40° 3' S., long. 132° 58' W. (Station 288) ; and lat. 5° 28' K, long. 

 14° 38' W. (Station 349). In the first-named locality only one specimen, a male, was 

 found ; in the second several specimens, all of which were females. A few specimens 

 were taken in Mid-Atlantic (Station 99), and mounted alive during the cruise, thus 

 preserving the colours of the living animal,- — the body a brilliant bluish-green, cornea 

 smoky yellow ; from all the spirit-specimens the colour has entirely fled. 



I have not been able to find the " falciform appendages " described by Dana ; probably 

 these correspond to the blunt frontal prominence wdiich I call the rostrum. Except 

 in the relative lengths of the antennal joints, the Challenger specimens agree closely 

 with Dana's description of Miracia ejferata, the anterior antenna of which is said to be 

 seven-jointed, the third, fifth, and seventh -joints being the shortest. I cannot at 

 all explain the discrepancy, and possibly the two may prove to be distinct ; but for the 



