110 



MR. C. F. U. MEEK ON THE CORRELATION OF 



the other members of the complex. Fio-. 1 shows a polar view of this 

 raetaphase, and seventeen chromosomes are seen in the equatorial plane. 



The last spermatogonial division is followed by a long period ot' growth, 

 and large tracts of the follicle are seen occupied by cells undergoing this 



stage. The chromatin is again disposed in 

 granules uj)on a network of linin threads, but 

 the odd chromosome takes no part in the general 

 dissociation and remains as a darkly staining and 

 homogeneous body apposed to the nuclear mem- 

 brane. The prophase of the first maturation 

 division is characterized by the fission of indi- 

 vidual granules and the breaking of the network 

 into numerous double filaments ; these, which are 

 at first long and ragged, conjugate in })airs and 

 condense into the usual tetrads, ap[)earing as rings, 

 crosses, and figures of eight. The closeness with which the component rods 

 are folded upon one another makes resolution extremely difficult, but size- 

 relationships corresponding with those seen on the spermatogonial spindles 

 are again recognizable, and each tetrad is undoubtedly composed of four 

 equal rods in juxtaposition. Since these rods are similar to those of the 

 earlier mitoses, the total amount of chromatin remains unchanged, and the 



Fip'. 2.— The Growth Period. 



Yigs. 3 & 4. — Polar and lateral views of first maturation mitosis. 



eight tetrads are collectively equivalent to the sixteen ordinary spermato- 

 gonial chromosomes. I have failed to determine whether this division is 

 reductional or equational, but this is immaterial, for either this or the next 

 mitosis must separate paternal and maternal elements. Figs. 3 and 4, repre- 

 senting respectively polar and lateral views of this division, show the eight 



