REVIEW OF GENUS ARGULUS — MEEHEAN 



511 



ARGULUS CATOSTOMI Dana and Herrick 



FiGxm.B 42 



Argulus catostomi Dana and Herrick, 1837, p. 297, pi. 1, figs. 1-11. — Milnb 

 Edwards, 1840, p. 445.— Thorell, 1865, p. 60.— Wilson, 1902, p. 709, pi. 13.— 

 Thiele, 1904, p. 25, figs. 53-58. 



Carapace orbicular, usually wider than long, about reaching abdo- 

 men; abdomen relatively small, rounded, with sinus one-fifth to one- 

 third the length. First antennae without spine at the base or on 

 ventral surface of hook; anterior knob present, flagellum with seta 

 opposing the distal segments; second antennae without a spine at the 

 base, spine present near midline of body. The respiratory areas are 

 composed of the smaller rounded one set in a notch mesially, about 

 the middle of the larger, and about opposite the second maxillae (fig. 

 42, a). The females have been reported up to 12 mm. long and the 

 males to 6 mm. 



■FiGDEE 42. — Argulus catostomi: a. Respiratory areas ; b, male accessory organs of last 

 three legs ; c, ribs of suction cups. 



