LACINULARIA SOCIALIS 



145 



Fig. 



6. Armature of the gizzard, viewed laterally. 



7. Termination of a water-vessel in the trochal disc. 



8. Water-vessel much magnified, showing the long flickering cilium. 



9. A portion of the ovary much magnified, showing the germinal vesicles with 



spots scattered through its substance. 



10. 11. Stages in the growth of the ovum. 

 12-18. Stages in the development of the embryo. 



19. Spermatozoon. 



Plate II. [Plate 15]. 



20. A portion of the ovary undergoing the change into an ephippial ovum 



21. 22. Ephippial ova, the latter having its contents divided into two portions 



23. Ephippial ovum burst. 



24. Its contents. 



25. Muscular fibre — relaxed, a ; contracted, l>. 



their 



26. 

 27. 

 28. 

 29. 



Melicerla ringens. 

 Viewed laterally. 

 From the ganglionic side. 

 From the mouth side. 

 Extremity of the calcar, showing its apparent closure and the bundle of cilia. 



30. Viewed laterally. 



31. From the mouth side. 



32. From the ganglionic side. 



33. From above. 



Brachionis polyacaidhics. 



Philodina^ sp. ? 



34. Trochal disc from above. 



35. laterally. 



36. From the mouth side. 



37. From the ganglionic side- 



Plate. III. [Plate 16]. 



The Diagrams illustrate Mr. Huxley's paper of Adult Rotifera, and of Larval 

 Annelids and Echinoderms. 



VOL. I 



