no. H04. PA RASITIC COPEPODS—CALIGID.E— WILSON. 561 



56. Genital segment rectangular; no lobes; free segment short and wide. 



dakari (van Beneden, 1892). 

 57. Females, both fifth and sixth legs visible; genital segment acorn-shaped. 



isonyx (Steenstrup and Li'itken, 1861), p. 602. 



57. Females, no legs visible on genital segment 58. 



57. Males, fifth legs concealed; genital segment narrow ovate, well lobed; emarginate 



posterii >rly chorinemi ( Kroyer, 1863) . 



58. Genital segment oblong, four times as wide as abdomen; no lobes; frontal 



plates projecting murrayanus (T. Scott, 1894). 



58. Genital segment elliptical, twice as wide as abdomen; no lobes; free segment 



long, narrow trachynoti ( Heller, 1 865 ) . 



58. Genital segment narrow obovate, well lobed; free segment short and broad. 



tenax (Heller, 1865). 



58. Genital segment oblong; lobes short, blunt; abdomen club-shaped; free'seg- 



ment long, narrow phipsoni (B-Smith, 1898, a). 



CALIGUS RUFIMACULATUS, new species. 



Plate V. 



Female. — Carapace more than half the entire length, elliptical, dis- 

 tinctly longer than wide, and scarcely narrowed anteriorly (fig. 51). 



Frontal plates large and wide, nearly straight along their anterior 

 border, and deeply incised at the center, where may nearly always be 

 found the remains of the frontal filament projecting from the incision. 

 Lunules large, almost circular, and widety separated, but not project- 

 ing very much. Posterior sinuses wide and inclined to the central 

 axis, leaving the median lobe more than half the entire width and 

 projecting considerably be3 T ond the lateral lobes. Lateral lobes nar- 

 row and curved inward at the tip. Free thorax segment small and 

 narrow, not distinctly separated from the genital segment, the divid- 

 ing groove being little more than a notch in either side, just back of 

 the fourth legs. Genital segment obovate, as wide as long, narrowed 

 anteriorly, with smooth, rounded outlines, and without appendages or 

 setae visible dorsal ly. 



Abdomen short and one-jointed, three-fourths the length of the 

 genital segment and about twice as long as wide; somewhat swollen at 

 the center into a spindle-shape. Anal lamina 1 large and stout. Egg 

 cases nearly as wide as the abdomen and about as long as the carapace, 

 35 or 40 eggs in each. 



Anterior antennae large and stout, the two joints about the same 

 length and heavily armed with plumose seta> and spines. Posterior 

 antenna' rather slender, but long, and with the terminal hook sharply 

 bent near the tip; a short and stout accessory spine present posterior 

 to the basal joint. First maxillae small and nearly straight, with a 

 swollen base. Second maxilla' also nearly straight and about as long- 

 as the rostrum; rather stout and blunt and considerably widened at 

 the base. 



