NO. 1302. A MERICAN PARASITIC A RG ULID.E— WILSON. 705 



Avhole length; anal papilla? basal. Disks of the anterior niaxillipeds 

 nearly one-third the width of the carapace; plate at base of posterior 

 niaxillipeds prolonged backward as a whole, without teeth or lobes; 

 ultimate segment longer than .the penultimate, hooks short and blunt. 



First antennae very short, without any hook on their anterior mar- 

 gin; second antennas also short; swimming legs all reaching be3"ond 

 the edge of the carapace. No flagella. Color 3^ellowish-white. 



Length, 2.3 mm.; length of carapace, 2.2 mm.; width of carapace, 

 2.5 mm.; length of abdomen, 0.7 mm,; breadth of abdomen, 0.45 mm. 

 Male unknown. 



6181. Vinej^ard Sound, Massachusetts; U. S. Fish Com., July, 1871; 



one female, the type, taken at the surface, . Casco Bay, 



Maine; U. S. Fish Com., 1873; one female, no data. 0184. Quahaug 

 Bay, Maine; host not given. 



{latus=-widG.) 



ARGULUS LATICAUDA Smith. 

 Plate X; Tlate XXVI, fig. 79. 



Arguliis laticauda Smith, Invertebrate Animals of Vineyard Sound, Eeport of 

 IT. S. Com. Fish and Fisheries, 1872. — Rathbun, Annotated List of Para- 

 sitic Copepods, Proc. U. S. National Museum, VII, 1884. 



Carapace elliptical, longer than wide; posterior sinus about one- 

 third the length of the carapace, twice as deep as wide. 



Abdomen orbicular, slightly longer than broad; anal sinus narrow, 

 extending scarce!}" a fourth the length; anal papillas basal. 



Disks of anterior niaxillipeds small, about one-eighth the width of 

 the carapace, placed well back; basal plate on posterior niaxillipeds 

 narrow, but expanding into a wide posterior margin, cut into three 

 broad, squarely truncated lobes. A papillated area near the center of 

 the plate; a row of spines along the posterior margin of the three 

 basal joints. Spines on the bases of the antennre large, broad, and 

 blunt. Males much larger comparatively than in other species, the 

 basal joints of their three posterior pairs of legs prolonged backward 

 into fleshy lobes, the outer ones narrow and linger-like, the inner ones 

 occupying the remainder of the joint. Flagella present. 



Length of male 5 to 6 mm.; length of carapace 3.5 to 4 mm.; width 

 of caraDace 3.2 to 3.5 nmi. ; length of abdomen 1.3 mm., breadth 1.1 

 mm. 



Smith's types were two females taken from among algse in Vineyard 

 Sound, Massachusetts, in August, 18T1 (Museum number, 0182). 



Since then the}" have been obtained in large numbers from various 

 fishes, those in the National Museum collection being numbered as fol- 

 lows: From the Eel {AnguiUa chrysypa Rafinesque), Nos. 1311, 1318, 

 and 1398, collected by V, N. Edwards; 6013^ 6013^ 6177, 8278, 8279, 

 12294; a lot from Katama Bay by Thompson, From Flatfish {Pseudo- 

 pleuronectes americanuH Walbaum), Nos. 1433, V. N. Edwards; 6152, 

 6171; a lot from Katama Bay by Thompson, another from Woods Hole 

 Proc. N. M. vol, XXV— 02 45 



