620 PROCEEDINGS OF THE NA TIOXAL MUSEUM. vol. xxxm. 



another pair of branches are given off at right angles to the median 

 axis. These are the same size and shape as the branchlets at the tip. 

 The first legs are three-jointed, ihe basal joint carrying a small spine 

 on its posterior border, a much larger one at the anterior distal cor- 

 ner, and a broad spathiilate spine in the middle of the ventral surface 

 at the distal end. The terminal joint has three short and stout ter- 

 minal claws and the usual plumose setse on its posterior border. 



The second legs are like those of Caligus, the spines on the exopod 

 being rather stout. The rami of the third legs are so close together 

 that they almost touch, the exopod three-jointed, the endopod two- 

 jointed. There is the usual large spine at the base of the exopod, a 

 very small one at the outer distal corner of the second joint and three 

 along the outer border of the terminal joint. 



The fourth legs are four-jointed with five spines, the inner terminal 

 one somewhat longer than the others, which are all about the same 

 size. The basal joint is stout and longer than the other three, which 

 are rather slender. 



Both the fifth and sixth legs are visible at the posterior margin of 

 the genital segment, the former on the vental surface a little in front 

 of the posterior end, the latter dorsal to them, but farther back at 

 the extreme tips of the posterior lobes. 



The reproductive organs and muscular system are similar to those 

 in Caligus. The ovaries are paired and situated over the oesophageal 

 portion of the digestive tract. The oviduct leads back to the gen- 

 ital segment, where it is coiled similarly to the condition in all the 

 Caligidse, but the coils are shorter than is usual in Caligus and 

 Lepeophtheirus. 



In the young females obtained from the pilot fish the condition 

 and coiling of these oviducts is peculiar (see fig. 91). 



In the posterior portion of the fourth or free segment the oviducts 

 enlarge more abruptly and to a greater diameter than is usual in the 

 Caligidae. In fact, on entering the genital segment the two oviducts 

 fill nearl}^ its entire diameter for the anterior third of its length. They 

 then narrow considerably, so that in the posterior half of the segment 

 there is room for three coils on either side. These oviducts are filled 

 for their entire length with a black granular and homogeneous mass 

 which is wholly opaque. Anteriorly the mass is divided into short 

 and wiile segments, corresponding to the future eggs, while posteriorly, 

 where the oviducts are much narrower, the segments at the sametime 

 increase in length. Their cubical contents are thus approximately 

 the same throughout the entire oviducts. The cement glands are 

 white in color, situated far forward in the genital segment, and quite 

 strongly curved parallel with the margin of the segment, thus giving 

 them the shape of ordinary parentheses marks. The glands them- 

 selves are wide, and the ducts leading from them are considerably 



