350 Cleland. — The Cytology and Life-history of 
Fig. 36. The threads present a granular appearance and show parallelism, suggesting fusion, 
x 2,200. 
Fig. 37. Thick spireme. Eight chromatic knots are beginning to form in the angles of the 
spireme, and will develop into the eight bivalent chromosomes, x 2,200. 
Fig. 38. Eight bivalent chromosomes, almost free from one another, x 2,200. 
Fig. 39. Bivalent chromosomes free, and now split, forming pairs of single chromosomes, x 2,200. 
Fig. 40. Diakinesis. Seven pairs of univalent chromosomes shown, x 2,200. 
Fig. 41. A zygote nucleus approaching mitosis with the polar structures made conspicuous 
through shrinkage of the surrounding cytoplasm, x 2,200. 
Fig. 42. Metaphase of the first mitosis which is the reduction division. The nucleolus is still 
present. The spindle is intranuclear, x 2,200. 
Fig. 43. Metaphase of the first mitosis, x 2,200. 
Fig. 44. After the first mitosis and before the cross-wall is formed, x 2,200. 
Fig. 45. Carpogonium divided into the sporogenous and hypogvnous cells, x 2,200. 
The Developing Cystocarp. 
Fig. 46. Sporogenous cell above with metaphase of the second mitosis. Food particles in 
a stalk-cell, x 2,200. 
Fig. 47. Metaphase in a gonimoblast initial, x 2,200. 
Fig. 48. Y oung cystocarp. x 1,520. 
Fig. 49. The proliferation of carpospore initials. New spores being developed in old cysts. 
X 1,520. 
Mitosis in the Cystocarp. 
Fig. 50. Resting nucleus with two nucleoli. Often seen in the cystocarp, but nowhere else, 
x 2,200. 
Fig. 51. Beginning prophase, x 2,200. 
Fig. 52. Later prophase. Many chromatic bodies, x 2,200. 
Fig* 53 * Still later prophase. The bodies become fewer by fusion, x 2,200. 
Fig. 54. Late prophase, showing chromosomes, x 2,200. 
Figs. 55, 56. Metaphases. Spindle intranuclear, with polar structures and nucleolus at the side 
of the equatorial plate, x 2,200. 
Figs. 57, 58. Anaphases, x 2,200. 
Fig. 59. Telophase. Spindle remnants still show, x 2,200. 
Fig. 60. Newly organized nuclei. Chromatin nucleoles suspended by fibrillae. All of the 
chromatin is contained still within these nucleoles. x 2,200. 
Figs. 61-5. Prophases and metaphase of the division which results in the cutting off of the 
first carpospore from a filament. Behaviour as in previous mitoses in the cystocarp (Figs. 51-6). 
x 2,200. 
PLATE XXIV. 
The Germination of the Carpospore. 
Fig. 66. A carpospore, the chromatophore with well-developed pyrenoid. x 2,200. 
Fig. 67. A carpospore in which the chromatophore has divided, x 2,200. 
Fig. 68. The effect of weak chromacetic acid on the pyrenoid. x 2,200. 
Fig. 69. Protrusion of the germ tube. Early prophase in the nucleus, x 2,140. 
Fig. 70. Early prophase. Polar structures have appeared, x 2,200. 
Figs. 71, 72. Mid-prophase. Many chromatic bodies. Polar structures shown in Fig. 72. 
X 2,200. 
Fig. 73. Late prophase. The chromatic bodies have condensed in number to eight chromo- 
somes. x 2,200. 
Fig* 74 * Just previous to metaphase. Chromacetic fixed. Note effect on pyrenoid. x 2,200. 
Figs. 75, 76. Metaphases. Spindles lying at different angles, intranuclear, x 2,200. 
Fig* 77 * Metaphase. Chromacetic fixed, x 2,200. 
Fig. 78. Anaphase. Chromacetic fixed. Note effect on pyrenoid, x 2,200. 
Fig. 79. Anaphase, x 2,140. 
