N0.1W2. AMERICAN PARASITIC ARGULID.E— WILSON. 721 



Sucking' disks very large, placed well forward and so close together 

 that they almost touch, about one-third the width of the carapace; 

 posterior niaxillipeds correspondingly small; l)asal plate rectangular 

 and armed with short blunt teeth. 



Antenna^- of medium size and well armed. Swimming legs not 

 reaching the edge of the carapace; lobes on the posterior ones small, 

 l)(>ot shaped. Flagella present but no papillae at the oviduct opening. 

 Male longer and much narrower than the female, particularly in the 

 abdomen; the carapace also in the male overlaps the a])domen, while 

 in the female it barely covers the third legs. 



Color a light liver-brown with a narrow dark margin anteriorly on 

 the upper surface of the carapace and a small dark spot tit the base of 

 the anal sinus. The grooves which separate the cephalic from the 

 lateral areas are darker and more 3^ellow in color than the rest of the 

 integument. The male lacks the dark anterior margin of the carapace 

 and the dark spot at the base of the anal sinus. 



Length 13 mm.; length of carapace 10.4 mm.; breadth of carapace 

 10. () mm.; length of al)domen 3.5 nmi. ; l)readth 2.6 nmi. 



llalrdat. — Brazil, South America, in the gill cavity of Salmo. 



{sahnlni^ from generic name of host.) 



ARGULUS CHROMIDIS Krbyer. 



Plate XXII, fig. 62. 



Argul.us chromidis Keoyek, Bidrag til Kundskab om Snyltekrebsene, Naturhist. 

 Tidskr. 3die Raekke, 2 Bind, 1863. — Thorell, Om tvenna Europeiske 

 Argulider, etc., (Efvers. af Kongl. Vetensk.-Akad. Forhandlingar, 21st 

 series, Stockholm, 1864. 



Carapace obovate, longer than wide, scarcely reaching the third 

 legs; posterior sinus so wide as to carry the lobes away from the 

 thorax and leave a clear space between, and reaching ])ut a quarter 

 the length of the carapace. 



Abdomen one-fourth the length of the rest of the body, about as 

 wide as long; anal sinus wide, well rounded, reaching a quarter the 

 length of the abdomen; papilke basal. 



Sucking disks small, about one-seventh the width of the carapace; 

 posterior maxillipeds small, ))asal plate rectangular, with short, blunt 

 teeth, the central one sharper than the others. Flagella present. 



The eggs occupy not merely the trunk, but nearly the whole shield 



(Kroyei')- 



Length 6 mm.; length of carapace 4.1 mm.; In-eadth of carapace 

 1 mm. ; length of abdomen 1.2 mm. ; breadth 1.1 mm. Male unknown. 



Color a clear yellowish-white, relieved by the dark coffee-brown 

 egg masses. 



Habitat. — Nicaragua, Central America, in the gill cavity of a species 

 of C?iromis taken from Lake Nicaragua. 



{chromidis from generic name of host.) 

 Proc. N. M. vol. XXV— 02 16 



