Conti, towards the Embryology and Anatomy of Poiistes pallipes. 211 



Fig. 26. Ovary E. Ovarian tubule from a yoimg pupa. The long distal 

 part, t, contains throiighout most of its length undifferentiated cells. x 100. 



Fig. 27. Three cells from the terminal portion of Ovary E; taken from 

 Position 27 in preceding figure. x 1600. 



Fig. 28. Two nuclei, a, from oöcyte, h, from primitive nurse-cell. Taken 

 from Position 28 in figure 26. x 1600. 



Fig. 29. Same a little further down the tubule, position 29. x 1600. 



Figs. 30, 31 and 32. Three cells, the first a primitive nurse-cell and the 

 other two developing nurse-cells. All from Ovary E at places represented by 

 corresponding numbers. x 1600. 



Figs. 33, 34 and 35. Mitotic figures from developing nurse-cells ; from the 

 middle part, oo, of ovary E. x 1600. 



Fig. 36. Nucleus of an epithelial cell from position 36 in figure 26. Line 

 to right represents wall of the tubule. x 1600. 



Fig. 37. Ovary F. Part of an ovarian tubule from a pupa ; the lines x—x 

 and Ä. — z represent the boundaries of its middle portion, ov; only a small piece 

 of the other two parts, distal and proximal is shown. x 100. 



Fig. 38. Cell from near the base of the distal portion of the tubule, from 

 Position 38 in ovary F. x 2000. 



Fig. 39. Two nuclei from the distal end of the median portion; from 

 place 38 in figure 37. a, of oöcyte, h, of primitive nurse-cell. x 1600. 



Figs. 40, 41 and 42. Three primitive nurse-cells, the last one just after 

 division. Taken from places in ovary F represented by corresponding figures. 

 X 1600. 



Fig. 43. Young oöcyte with beaded chromosomes; from position 43 in 

 figure 37. x 1600. 



Fig. 44. Same a little older, first before synapsis. x 1600. 



Fig. 45. Oöcyte and nurse-cells from position 45 in ovary F. a, oöcyte 

 in synapsis; h, fully developed nurse-cell after division has entirely ceased. 

 X 1600. 



Fig. 46. The oldest oöcyte and nurse-cell in ovary F. a, oöcyte, nurse- 

 cell. X 1600. 



Plate XIII. 



Fig. 47. Ovary G. Two nuclei, a, oöcyte, b, primitive nurse-cell from 

 older tubule; from position corresponding to figure 40 in ovary F. x 1600. 



Fig. 48. Oöcyte nucleus, a, and primitive nurse-cell, 6, from position 

 slightly proximal to the last, x 1600. 



Fig. 49. Primitive nurse-cell in chromosome stage; from ovary Gr. x 1600. 



Fig. 50. Oöcyte in chromosome stage; to the left part of another oöcyte, 

 and between the two, a double chromatin ring, x 1600. 



Fig. 51, Oöcyte, a, and nurse-cell, from proximal end of the middle 

 portion of ovary G. x 1600. 



Fig. 52. Ovary H. Part of the middle portion of an ovarian tubule in 

 which the first Chamber is being formed. Proximal to the oldest oöcyte, 56, is 

 the beginning of the oviduct. Syn, region in which synapsis occurs. x 200. 



Fig. 53, 54 and 55. Three oöcyte nuclei from positions represented by 

 same figures in ovary H. x 1600. 



Fig. 56. Oldest oöcyte in ovary H. Only a small amount of cytoplasm in 

 the neighborhood of the yolk-nucleus has been drawn. x 1600. 



