1899] LIFE-HISTORY OF LEMNA MINOR 47 
the left of the two stamens in fig. rg. After.a short time each 
of these groups of archesporial cells is divided in the same 
way, thus producing the archesporial masses of the four loculi 
of the stamen. This condition is shown in the older stamen of 
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Fic. 13. Young stamen with archesporial tissue. X 1375. 
Fic. 14. Two young stamens; in one the archesporial tissue is becoming divided 
by a sterile plate ; beginning of the spathe is seen. X 890 
Fic. 15. Same as Jig. 14 but more advanced. X 8g0. 
Fic. 16. One stamen showing the four loculi well separated. X 890. 
Jig. 15, while the younger stamen of this figure has its arche- 
Sporium divided into two masses. 
In an examination of later stages in the development of 
these tissues it wil] be seen that the separating region continues 
to develop new cells until the usual amount of sterile tissue 
between the fully formed loculi may be seen (fig. 76). In the 
