688 A NBW ENDOPAUASITIC COPEPOD. 



Fig.25. — Transverse section at the level of the posterior end of the alimen- 

 tary canal (a/.). 



Fig. 26. — Two cells from the digestive(?) gland related to the second com- 

 partment. 



Fig. 27. — Transverse section at the level of the external orifice of the vas 

 deferens(a/). ) and tiie vesicula seminali8(r.s.). 



Fig. 28. — Vas deferens in transverse section. 



Fig.29. — Pjpithelium of the oviduct. 



Fig. 30. — Portion of the section drawn in Fig.27, under higher magnification: 

 vas., vas deferens. 



Fig. 31. — Transverse section at the leTel of the vulva (r\) on one side: 

 s.yL, slime-gland. 



Fig. 32. —The region of vulva(('.) Mux., plain niuscle-hundles. 



Plate Ixx. 



Fig. 33. — The two-celled embr^'o, transverse section. 



Fig 34. — The four-celled embryo, transverse section. 



Fig. 35. — The sixteen-celled embryo, transverse section. 



Fig.36. - The sixteen-celled embryo, longitudinal section. 



Fig.37. — The sixteen-celled embryo, longitudinal section. 



Fig. 38. — The thiity-two-celled embryo, transverse section. 



Fig.39. — The gastrulation period of development, longitudinal section. 



Fig. 40. — The gastrulation period of development, transverse section. 



Fig.41. — Longitudinal coronal section of the late gastrula. 



Fig. 42. — The very early nauplius(A', antennule; A", antenna; 7im., man- 

 dible; mes., mesoderm; g., primodial germ-cell). 



Fig. 43 — A more advanced nauplius(e. , eye). 



Fig. 44.— The nauplius(/6)-., labrum). 



Fig. 45. — The nauplius, nearly' median coronal section (oc, retinal celh ; 

 br., brain; nph., larval kidney). 



Fig. 46. — The nauplius, median sagittal section (end., endoderm; ?«?*.%•., 

 skeletal muscles). 



