PLATE 20.— Entomostraca. 



Figure 



1. Argulus foliaceus, seen from beneath, a, anterior, b, posterior antennae ; c, 



rostrum ; d, suckers, representing the first pair of legs ; e, second pair of legs ; 

 /, four posterior pairs of legs. 



2. Bosmina longirostris ; 2*, the same, natural size. 



3. Branchipus stagnalis. 



4. Camptocercus macrourus. 



5. Cypris reptans ; 5 a, inferior antenna. 



6. Canthocamptus minutus ; 6a, inferior antenna; 6 b, first pair of foot-jaws 



6c, second pair of foot-jaws. 



7. Chydorus sphcericus. 



8. Cyclops qiiadricomis, male, a, b, superior antennae 



9. Cyclops quadricornis, female. a, superior, b, inferior antennae. 



10. Cyclops quadricornis, inferior antenna. 



11. Cyclops quadricornis, mandible ; a, body ; b, serrated seta ; c, filaments of palp. 



12. Cyclops quadricornis, first pair of foot-jaws. 



13. Cyclops quadricornis, second pair of foot-jaws: 13 a, internal portion; 13 6, 



external portion. 



14. Cyclops quadricornis, first pair of thoracic legs. 



15. Cyclops quadricornis, fifth pair of legs. 



16. Cyclops quadricornis, recently hatched. 



17. Cyp7-is tristriata. 



18. Cypris tristriata, superior antenna. 



19. Cypris tristriata, inferior antenna. 



20. Cypris tristriata, mandible. 



21. Cypris tristriata, first pair of jaws ; a, basal plate ; b, branchial lamina. 



22. Cypris tristriata, second pair of legs. 



23. Cypris tristriata, first pair of legs. 



24. Cypris tristriata, second pair of legs. 



25. Cypris tristriata, lateral half of the abdomen. 



26. Cythere inopinata. 



27. Baplmella Wingii, 



28. Daphnia pulex. a, superior antennae ; b, inferior antennae ; c, heart. 



29. Daphnia pulex, first pair of legs. 



30. Daphnia pulex, second pair of legs. 



31. Daphnia judex, third pair of legs. 



32. Daphnia pulex, fourth pair of legs. 



33. Daphnia pulex, fifth pair of legs. 



34. Daphnia pidex, mandible. 



35. Daphnia pidex, labrum. 



36. Daphnia pulex, jaw. 



37. Daphnia, reticulata, a, ephippium. 



38. Diaptomus castor. 



39. Eurycercus lamdlatus. 



