732 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxv. 



The ovary is also similar, being- unsymmetrical and occupying the 

 center of the ventral surface. 



In the male the testes are much larger than in Argulus, but occupy 

 the same position, while we lincl on the two posterior pairs of legs the 

 accessory peg and semen receptacle as in the former genus. 



The chief distinctions l)etween the two genera, therefore, are con- 

 fined to the anterior maxillipeds and the mouth parts, as given in the 

 artificial key herewith presented. 



DOLOPS LONGICAUDA Heller. 

 Plate XXV, tig. 76. 



Gyrnpellh Imui'irandd Heller, 1857. 

 Gj/rnprlli^ IniHjiciiuhi Kroyer, 1863. 

 Gi/nqH'/tix lnii,jir(injl<t Thorell, 186-4. 

 DolopK longicauda Bouvier, 1899. 



Carapace orbicular, as broad as long; posterior sinus one-fifth the 

 length of the carapace, as broad as long. 



Abdomen very long and narrow, one and one-half times the length 

 of the rest of the body; anal sinus broad trianugular, cut clear to the 

 base, leaving the lobes very narrow-acuminate and flaring at the tips. 

 Anterior maxillipeds short with few joints, terminated by a stout 

 hook; posterior maxillipeds stoitt; Imsal plate with three sharp teeth 

 close together. 



Swimming legs rather small; lobes on posterior pair large and wide. 

 Each testis divided longitudinally into two lobes united at their bases; 

 accessor}' copulatory organs consisting of two finger-like projections 

 from the anterior surface of the basipods of the third pair of legs. 



Flagella present. In the male the testes are two-lobed and there 

 are lobes on the posterior ])order of the basal joints of the third legs 

 in addition to the regular peg and capsule. 



Color a dark ashy-gray, with a line of pigment around the edge of 

 the carapace and along the inner border of the abdomen lobes. 

 Length 2S mm. ; length of carapace 1'2 mm. ; width of carapace 12 mm. ; 

 length of abdomen Ki mm.; breadth of each lobe at the widest place 

 1.9 mm. Male aT)out the same size. 



Hahitat. — In Brazil on the gills of I[ydrocyon (Salmo) hrew'dens, 

 C'uvier. 



{longa=^]ong, caud<( = tii\] (abdomen).) 



DOLOPS KOLLARI Heller. 

 Plate XXV, lig. 77. 



Gyropelth l-(ilJ<iri Heller, 1857. 

 Gyropdtls kullarl Kroyer, 1863. 

 Gyropeltk hollari Thorell, 1864. 

 Dolopii kollari Bouvier, 1899. 



Carapace large, obcordate, covering all the legs and the base of the 

 abdomen; posterior sinus shallow, one-seventh the length of the cara- 



