no. 1404. PARASITIC COPEPODS— CALIGID.fi— WILSON. 595 



Frontal plates narrow, a little more than half as wide as the cara- 

 pace; hinnles large, circular, but almost entirely concealed in dorsal 

 view, appearing only as a slight concavity at the base of the first anten- 

 nae. Posterior sinuses broadly triangular, the median lobe consider- 

 ably less than half the entire width. Thoracic area rather small, not 

 quite reaching the center of the carapace. Digestive glands situated 

 at about the center of this area, each in the form of a large right- 

 angled triangle, the perpendiculars parallel with the longitudinal axis, 

 the bases at the posterior ends. 



Free thorax segment narrow and short, swollen considerably at the 

 center where the fourth legs are attached. Genital segment broad 

 acorn shape, narrowed into a slender neck where it joins the free seg- 

 ment and squarely truncate posteriorly. 



It is two-thirds as wide as the carapace and the sides and posterior 

 corners are symmetrically rounded. 



Abdomen. as long as the carapace, the length three and a quarter 

 times the width, slightly swollen at the center and constricted where 

 it joins the genital segment. It is two- jointed, the first joint being 

 four times the length of the second. 



In living specimens and in material preserved in formalin the joints 

 are distinct, but in material preserved in alcohol they become indis- 

 tinct. But in all specimens alike the abdomen is abruptly narrowed 

 at the groove between the joints, the terminal joint being considerably 

 narrower than the basal, and tapering posteriorly. Anal lamina? of 

 medium size, and flattened, with the tips turned in toward each other. 



Egg strings wide, considerably shorter than the body, each contain- 

 ing about thirty eggs. 



First antennas small, the basal joint short and not very wide, but 

 heavily armed with seta?; the terminal joint short, club-shaped, and 

 scarcely projecting beyond the edge of the carapace. 



Second antenna? with a very long and slender terminal claw, and 

 without any accessory spine at the base. 



First maxilla? very small with a narrow, blunt tip and a slightly 

 swollen base. Second maxilla 1 long and acuminate, projecting some 

 distance beyond the tip of the rostrum. 



Second maxillipeds with a stout basal joint, somewhat swollen, and 

 a much shorter and rather slender terminal claw. 



Furca short, the base not more than half as wide as the branches; 

 (he latter simple, short, very wide, and curved. 



The first natatories have a long plumose seta on the distal end of the 

 basal joint, a short curved claw at the distal end of the second joint, 

 while the terminal joint carries three very large plumose seta? on the 

 posterior margin, and the usual terminal claws. The latter are all 

 curved, about the same size, and close together. In addition there is 

 a finger-like projection extending from the distal margin in the same 



