NO. 1788. NORTH AMERICAN EROASILID.^— WILSON. 375 



First swimming legs with a one-jointed exopod, triangular in shape, 

 and armed v/ith six flattened plumose setae along its posterior mar- 

 gin and a single spine on its anterior margin. Endopod made up of 

 three joints, the first without spines or setse, the second with a single 

 large seta on its inner margin, the third with five sette. Exopods of 

 second, third, and fourth legs distinctly four-jointed, endopods three- 

 jointed. Endopod of the second pair with the flattening of the joints 

 and setae carried to such a degree that it seems as if it must be abor- 

 tive. And yet it is alike on the right and left sides and on the two 

 specimens at command. Each joint is much widened and flattened, 

 very similar to those of the first legs; the setae with which they are 

 armed are also widened and flattened like those on the first legs (see 

 fig. 180). The arrangement of the spines and setae is as follows: 

 Second exopod, I-O; I-l; II-2; II-3: endopod, 0-1; 0-1; 0-2: third 

 exopod, I-O; I-l; I-l; II-3: endopod, 0-1; 0-1; 0-4: fourth exopod, 

 I-O; I-O; I-O; II-4: endopod, 0-1; 0-1; 0-3. Fifth legs two-jointed, 

 the basal joint short and narrow, the terminal joint four times as long, 

 enlarged into a spatulate form, and tipped with three nonplumose 

 setae, of which the central one is three times the length of the other 

 two. 



Total length, 2.2 mm. Cephalothorax, 0.77 mm. long, l.lcS mm. 

 wide. Length of free segments, 0.87 mm.; of genital segment and 

 abdomen, 0.55 mm.; of anal setae, 0.55 mm.; of egg-cases, 1.1 mm. 



Color a rich seal brown inclming to reddish, lighter on the ventral 

 surface. 



(nitidus, neat, tasty in appearance.) 



The National Museum collection includes but a single lot of this 

 species, obtained from the gills of the common mullet Mugil ceplialus, 

 at Beaufort, North Carolina, in 1905. 



This lot is numbered 38611, U.S.N.M., and consists of two females 

 which are made the types of the new species. 



These parasites are not at all common, since the examination of 

 several hundreds of fish yielded only the two specimens. They were 

 found in company with Ergasilus mugilis Vogt. 



BOMOLOCHUS SOLEiE Claus. 



Plate 57, text-figure 40. 



Bomolochus soleae, Claus, 18G4, p. 374, pi. 25, figs. 16-20.— T. Scott, 1902, p. 288, 

 pi. 13, figs. 13-18.— A. Scott, 1904, p. 117. 



Male. — General body form elongate and narrow; first thorax seg- 

 ment distinctly separated from the head; carapace (cephalon) cir- 

 cular, abruptly narrowed anteriorly between the bases of the first 

 antennae, elsewhere evenly rounded. 



