THE HIGHER CRYPTOGAMIA. 403 



The numerous amyloid granules of the cell-sap, accumu- 

 late, after the production of two secondary nuclei, in the 

 form of an annular girdle in the equator of the cell. This 

 girdle soon divides into two, parallel to one another 

 (PL LIX, fig. 3). The division of the cell-contents into 

 two halves appears thus to be indicated. These conditions 

 are so frequent that I do not doubt they must occur in all 

 mother-cells. The further formation, however, takes place 

 in two different ways. The case of least frequent occur- 

 rence is as follows : — A delicate line suddenly appears in 

 the equator of the cell between the two girdles of granules, 

 which line immediately disappears under the action of 

 strong reagents. I believe the line to indicate the surface 

 of contact of the two membraneless halves of the cell- 

 contents produced by the division of the contents of the 

 mother-cell. Shortly afterwards a circular ridge makes its 

 appearance, seated upon the inner wall of the mother- cell 

 and traversing its equator, and forming as it were a frame to 

 the septum of the two special-mother- cells of the first degree 

 which are in course of formation. The other case above 

 alluded to, and which is the one of ordinary occurrence, is 

 the following: — The division of the primordial utricle is in- 

 terrupted by the fact that the membranes of the secondary 

 nuclei are absorbed, and in the place of each one of them, 

 two — making four altogether— perfectly spherical nuclei are 

 formed, which either lie in one plane, or are arranged at the 

 angles of a tetrahedron. Between each two of these, 

 flattened accumulations of granules are produced, in each 

 of which a delicate line suddenly becomes visible, which is 

 the first indication of the septum dividing the two special- 

 mother-cells. 



After the formation of two special-mother-cells of the 

 first degree, two cells are formed in each of them, so that 

 then each set of special-mother-cells consists of four. 



Pinus Larix differs somewhat from other Coniferae in the 

 circumstance that in one way or another more than four 

 special-mother-cells and pollen-cells are frequently, in fact 

 almost always, formed in one mother-cell. The usual 

 number is six, and the occurrence of seven or eight is 

 not unusual (PL LIX, fig. 6). 



