62 Franz Sclirader, A study of the Chromosomes in tliree species of Pseudococcus. 
Fig. 39. Spermatozoon heads with cytoplasm being sloughed off. 
Fig. 40 a and b. Oogonial plates, ten chromosomes. 
Fig. 41a and b. Spermatogonial chromosomes shortJy before plate formation. 
Ko clumping. 
Pseudococcus nipae. 
Fig. 42. Resting stage in spermatogonial cell. 
Fig. 43 a and b. Metaphase plates of spermatogonia, showmg two groups. 
Fig. 44. Metaphase plate of first spermatocyto, showing two groups. 
Fig. 45. Anaphases of seeond spermatocyto di\nBion. 
Plate VI. 
Pseudococcus maritimus. 
Fig. 46 a and b. Early somatic nuclei — previous to blastula stage. 
Fig. 47. Abnormal cell with multiple number of chromosomes. 
Fig. 48. Probable origin of abnormal cells from a fusion of several cells. 
Fig. 49. Chromosomes of cell in a gastrula. 
Fig. 60. A’erv'ous tissue of male. Cells showing Condensed chromatin. 
Fig. 51. Nervous tissue of female. No condensation. 
Fig. 62a, b, c and d. Successive phases in the evolution of chromosomes of somatic 
cells in the wing pad of a male. 
Fig. 53. Pseudococcus citri. The five tetrads in the maturation of the egg. (Magni- 
fication: 2000.) 
