PLATE 20 



Fig. 37. Late anaphase in which eeutrioles and part of the central spindle 

 may be distinguished. 



Fig. 38. Peripheral chromatin free from nuclear membrane and taking posi- 

 tion on karyosome. 



Fig. 39. Early prophase with peripheral chromatin moving into the karyo- 

 some which is elongated. 



Fig. -to. Nucleus in dividing material showing darkly stained peripheral 

 chromatin, some of which is connected by lines with the karyosome. 



Fig. 41. Polar view at small angle showing relation of karyosome and 

 spindle chromatin. 



Fig. 42. Early anaphase. Polar caps, chromosome granules, centrioles in 

 centrodesmose, and central spindle. 



Fig. 43. Fusion of chromatin masses with traces of centrodesmose showing, 

 peripheral chromatin in state of being extruded, remains of nuclear connection 

 persisting. Karysome and nucleus not rounded. 



Fig. 44. Early prophase with enlarged nucleus, evident peripheral chromatin, 

 and large vacuolated karyosome. 



Fig. 45. Peripheral chromatin is fibrillar and is on the side of the elongated 

 bending karyosome. 



Fig. 46. Reorganizing nucleus. Two chromatin masses fused into karyosome 

 which is elongated and vacuolated. Peripheral chromatin connected with karyo- 

 some. 



Fig. 47. Spindle turned showing chromatic polar mass connection on one 

 side. Spindle fibers, with chromatin granules, between the two ends. 



Fig. 48. Spindle at the beginning of the metaphase showing indications of 

 polar caps, equatorial plate, centrioles, and central spindle. 



Fig. 49. Dumb-bell neck at upper surface. 



Fig. 50. Early reorganization. The two masses of chromatin separate, 

 peripheral chromatin being extruded. 



Fig. 51. Daughter nucleus at telophase. Chromatin masses fused but nuclear 

 membrane not closed. Extrusion of peripheral chromatin from one side. 



Fig. 52. Late prophase showing two polar caps, granular chromatic polar 

 masses, centrioles, and centrodesmose. 



Fig. 53. Nucleus reorganizing after division. Peripheral chromatin nearly 

 all extruded, two chromatin masses fused but not rounded up and a central 

 vacuole or centrodesmose. 



Fig. 54. Early prophase. Karyosome, with ends pointed, is constricted and 

 peripheral chromatin is moving into angle between the chromatic polar masses. 



Fig. 55. Section view of nucleus of figure 41, showing granular nature of 

 the chromatin, and the continuity of the polar and the chromosome chromatin. 



Fig. 56. Surface view of side of spindle showing the same thing. 



Fig. 57. A reorganizing nucleus which resembles amitosis. 



Fig. 58. Two nuclei of which the one above is comparable to that of figure 

 43, but is a little later. The other one either did not divide or is nearer re- 

 organization. 



Fig. 59. Centriole showing in karyosome. 



Fig. 60. Late prophase viewed from the side showing the chromatic polar 

 mass connection on the surface. Spindle is below. 



Fig. 61. Later reorganization. Peripheral chromatin at the nuclear mem- 

 brane. Vacuole prominent. 



Fig. 62. Early prophase nucleus showing two centrioles and central spindle. 



Fig. 63. Cyst with two nuclei. Wall showing much darker. Drawn from life. 



Fig. 64. Encysted individual with a small nucleus in which the karyosome 

 is compact and a large nucleus in which the karyosome is broken up. Wall 

 omitted. 



Fig. 65. Encysted amoeba in which the karyosome is broken up. 



Fig. 66. Encysted amoeba in which the karyosomes of the two nuclei are 

 broken up. 



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