68 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.53. 



but in the genital segment, where it is somewhat enlarged, it lies 

 near the dorsal surface and leaves room for the oviducts and cement 

 glands. 



Color a dull, yellowish-white, often becoming transparent in the 

 neck and abdomen, head a bright p,ink red, egg strings a beautiful 

 maroon on ripening ; large blotches of the same maroon on the basal 

 joints of the legs, the rows thus formed continued forward onto the 

 head; oviducts dark brown. 



Total length, excluding egg strings, 40 to 50 mm. Length of head, 

 2.35 mm. ; of neck, 25 mm. ; of genital segment, 5.50 mm. ; of abdo- 

 men, 10 mm. ; of egg strings, 13 mm. Diameter of neck, 0.45 mm. ; of 

 genital segment, 1.30 mm.; of abdomen, 0.35 mm.; of egg strings, 

 0.30 mm. 



{longiventris, longus, long and venter, abdomen.) 



Nauplius. — Body spindle-shaped, the posterior half considerably 

 narrower than the anterior, both ends evenly rounded, the length 

 to the width at the center as 10 to 7. The eye spot is comparatively 

 large and shaped like the section of an ordinary T rail. There are 

 four color spots, a large one at the center on either side close to the 

 lateral margin and a pair of smaller ones near the posterior end, 

 each about half way between the margin and the midline. These 

 four and the eye spot are the same rich maroon red as is found on 

 the basal joints of the legs of the adult. 



In the center of the body are oil globules, sometimes a single large 

 spherical one filling the whole center, as in figure 70, sometimes a 

 pair of smaller ones with their adjacent sides flattened along the mid- 

 line. 



Occasionally there is a group of small drops irregularly disposed, 

 but always chiefly at the center. The balancers are large and stout, 

 and are curved forward on either side. 



Length, 0.25 mm. ; width at the center, 0.175 mm. 



Remarks. — This species was first found upon the crevalle or hard 

 tail, Garanx cri/sos, the genital segment and egg strings showing on 

 one side or the other of the dorsal or ventral fin near the tail. After- 

 wards a single specimen was taken from the operculum of the com- 

 mon mullet, 3Iugil cephalus, and several specimens near the dorsal 

 and anal fins of the small dolphin, Coryphaena equisetus. The head 

 is buried in the tissues close to the backbone, where it forms a fibrous 

 membrane or sheath, very tough and fitting so tightly that it is dif- 

 ficult to remove it without injury to the head of the parasite. The 

 neck is contractile and upon irritation can be withdrawn, pulling 

 half or two-thirds of the genital segment in with it. When the irri- 

 tation stops the body returns to its normal position. The species is 

 not at all common and only a single specimen has been found upon 

 any fish. 



