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EXPLANATION OF PLATES XV AND XVI. 
Illustrating Professor Allen’s paper on the Spermatogenesis of Polytrichum juniperinum. 
The figures were drawn with the aid of a camera lucida, the drawing being at the level of the 
base of the microscope ; some of them with a Zeiss 2 mm. apochromatic objective, 1*40 N.A., and 
compensation ocular number 18 ; the others with a Leitz 2 mm. apochromatic objective, 1*32 N.A., 
and compensation ocular number 18. In each case the magnification is about 3800 x . 
PLATE XV. 
Figs. 1, 2. Pairs of young sister androcytes, each showing a blepharoplast in the region 
occupied by a pole of the spindle in the division recently completed. 
Figs. 3, 4. Single androcytes ; the blepharoplast in each has grown somewhat. 
Fig. 5. An androcyte whose blepharoplast has become a short rod ; the limosphere also visible. 
Figs. 6-10. Stages in the elongation of the blepharoplast; the limosphere visible in Figs. 9 
and 10. 
Figs. n-13. Androcytes with still longer blepharoplasts and distinct limospheres. At the 
upper end of Fig. 13 two unusually large androcytes. 
Figs. 14-19. Different views of androcytes all at about the same stage of development; the 
blepharoplast has become a curved rod, lying in a peripheral position with one end close to the 
limosphere. 
Fig. 20. An androcyte containing a double (or dividing) limosphere ; the blepharoplast is not, 
at least for a considerable part of its length, peripheral. 
Figs. 21-4. Stages in the division of the limosphere. The lowermost androcyte represented in 
Fig. 24 shows an unusual (perhaps abnormal) condition of the limosphere. 
Fig. 25. The apical body is now separated from the limosphere. 
Fig. 26. The limosphere is moving away from the region in which the apical body was cut off 
from it. 
PLATE XVI. 
Fig. 27. The limosphere is in contact with the nucleus; the dark object lying over the apical 
body is probably the perenosome. 
