NO. 2063. NORTH AMERICAN PARASITIC COPEPODS— WILSON. 671 



TABLE OF SPECIES. 



1. Cephalothorax definitely longer than the trunk 2. 



1. Cephalothorax about the same length as the trunk or shorter 8. 



2. Trunk as wide as, or wider than, long; base of neck somewhat differentiated from 



the rest of the thorax; second maxillae lacking, bulla on the body; egg strings 



long, tapering 3. 



2. Trunk as wide as, or wider than, long; base of neck not differentiated; second 

 maxillae as long as the cephalothorax; egg strings short and stout 4. 



2. Trunk definitely longer than wide; base of neck not differentiated; second max- 



illae lacking, bulla on the body; egg strings long and tapering 5. 



3. Genital process exceptionally large and prominent; maxillipeds small; head 



pointed; egg strings straight perfida, new species, p. 672. 



8. Genital process medium-sized; maxillipeds small; head swollen and bluntly 

 rounded; each egg string curled until its ends nearly touch each other. 



characis (Richiardi), 1880, p. 668. 



4. Second maxillae completely fused; neck smooth; genital process large. 



inversa Wilson, 1912, p 673. 

 4. Second maxillae separate at their bases; neck and arms very rough; genital proc- 

 ess minute pagri (Kr0yer), 1863. 



4. Second maxillae separate at their tips; neck and arms smooth; genital process 



minute stichaei (Kr0yer), 1863. 



5. Cephalothorax flexed back so tightly as to form a longitudinal groove on the 



dorsal body surface; head swollen; egg strings long and slender 6. 



5. Cephalothorax not turned back against the trunk; no dorsal groove; head not 



enlarged ; egg strings short and stout 7. 



6. Second maxillae entirely lacking; trunk pear-shaped, much narrowed and 



■wrinkled anteriorly; genital process minute agilis (Kr0yer), 1863, p. 668. 



6. Second maxillae very short; trunk ovoid or ellipsoidal, smooth and plump; gen- 

 ital process minute bergyltae (Kr0yer), 1863. 



6. Second maxillae entirely lacking; trunk oblong, no wrinkles; genital process one- 

 third the length of the trunk tumida, new species, p. 674. 



6. Second maxillae one-third the length of the cephalothorax; trunk ovoid, not 



wrinkled; genital process of medium size canaliculata, new species, p. 675. 



7. Second maxillae entirely lacking; cephalothorax stout and wrinkled posteriorly; 



genital process of medium size parva Wilson, 1912, p. 676. 



7. Second maxillae entirely lacking; trunk nearly spherical; genital process minute. 



canthari (Heller), 1865, p. 669. 

 7. Second maxillae quarter as long as cephalothorax; trunk ellipsoidal, twice as 



long as wide; genital process wanting insolita, new species, p. 676. 



7. Second maxillae half as long as cephalothorax; trunk ovoid, nearly three times 



as long as wide; genital process wanting levis, new species, p. 677. 



8. Genital process lacking; second maxillae medium length 9. 



8. Genital process present; second maxillae short, often lacking 11. 



9. Trunk as wide as, or wider than, long; second maxillae partly or wholly sepa- 



rated angulata (Kr0yer), 1863, p. 668. 



9. Trunk distinctly longer than wide; second maxillae completely fused for their 

 entire length : 10. 



10. Trunk ellipsoidal, twice as long as wide, and evenly rounded; bulla a large flat- 

 tened disk with stellate perforations stellata (Kr0yer), 1838, p. 670. 



10. Trunk ellipsoidal, twice as long as wide, and evenly rounded; bulla minute 

 and spherical pinguis, new species, p. 678. 



10. Trunk pear-shaped, three times as long as wide; second maxillae covered with 

 scales squamigera, new species, p. 679. 



