A Comparative Study of tlie Structure and Origin of the Yolk Nucleus. 715 
Fig. 27. Vitelline body or yolk nucleus from oocytes of Limulus polyphemus, 
2 x 1 / 6 , c. 
Fig. 28. Vitelline body, egg of Limulus , 1 x y 6 . 
Fig. 29. Vitelline body, egg of Limulus. 
Fig. 30. Vitelline body, egg of Limulus, 1 x 1 / fi , c. 
Fig. 31. Vitelline body (yolk nucleus) of Limulus, 2 x V 12 , c. 
Fig. 32. Aster and centrosome of ovarian egg, Limulus. 
Fig. 33. Vitelline body (yolk nucleus) of Limulus. 
Fig. 34. Vitelline body (yolk nucleus) of Limulus. 
Fig. 35. Vitelline body (yolk nucleus) of Limulus, 2 x y 12 , c. 
Fig. 36. Vitelline body (yolk nucleus) of Limulus. 
Fig. 37. Vitelline body (yolk nucleus) of Limulus. 
Plate XXXII. 
Fig. 38. Ovarian egg of Limulus, showing ring around the germinal vesicle, 
2 x Ve, c. 
Fig. 39. Ovarian egg of Limulus, showing vitelline body (yolk nucleus) with 
centrosome and aster, 2 x V 6 , c. 
Fig. 40. Oocyte of Limulus, showing vitelline body in form of aster, 2 x V«, c. 
Fig. 41. Vitelline body (yolk nucleus) of Limulus, 1 x V12, c. 
Fig. 42. Large ovarian egg, showing the sphere and aster of Limulus, 1 x Vs, c. 
Fig. 43. Ovarian egg of Limulus, showing dark granulär ring around germinal 
vesicle. 
Fig. 44. Vitelline body (yolk nucleus) of Limulus, 1 x Ve, c. 
Fig. 45. Vitelline body (yolk nucleus) of Limulus, 2 x Ve, o. 
Fig. 46. Ovarian egg of Limulus, (gold Chloride), showing minute structure of 
vitelline body, concentric zones seen separated by a line, 2 x Ve, c - 
Fig. 47. Vitelline body (yolk nucleus) of Limulus, 1 x Ve, c. 
Fig. 48. Ovarian egg of Limulus, 1 x V 3 , c. 
Fig. 49. Vitelline body (yolk nucleus) of Limulus. 
Plate XXXIII. 
Fig. 50. Ovary of pigeon, in section, showing oocytes and yolk nucleus, centro- 
some and aster. 
Fig. 51. Oogonium of pigeon, showing centrosome. 
Fig. 52. Ovarian egg of pigeon, showing yolk nucleus as aster and centrosome, 
1 x Ve, c. 
Fig. 53. Oocyte of pigeon, showing spherical body with a distinct centrosome. 
Fig. 54. Ovarian egg of goosefish, with yolk nucleus, 2 x Ve, c - 
Fig. 55. Oocyte of fish with yolk nucleus. 
Fig. 56. Ovarian egg of cat with yolk nucleus and centrosome. 
Fig. 57. Egg of fish with large yolk nucleus, looking like archoplasm. 
Fig. 58. Cytoplasm of degenerating eggs of Limulus, containing real nuclei. 
granules partly absorbed. 
Fig. 59. Cytoplasm of ovarian egg of Limulus, containing real nuclei, beginning 
degeneration. 
Fig. 60. Egg of fish with large yolk nucleus, 2 x Vi 2 - 
Fig. 61. Vitelline body (yolk nucleus) of ovarian egg of Limulus. 
Archiv f. Zellforschung VIII. 47 
