3 1 8 KING. [Vol. XV 1 1 . 



somewhat distorted and its fibers appear granular and very- 

 indistinct. 



The first polar body (PI. XXX, Figs. 35-37) is usually oval, 

 rarely round. It is surrounded by a thin delicate membrane, 

 and contains chromatin, cytoplasm, pigment granules, and 

 occasionally yolk spherules. The chromosomes are soon col- 

 lected in an irregular-shaped m.ass in the center of the polar 

 body and every trace of their individuality is lost. I have seen 

 no indication of a later division of the first polar body as has 

 been observed by Fick in Axolotl and by Korschelt in Ophryo- 

 trocha. 



The first polar division occurs while the egg is in the ovi- 

 duct, and here too the egg receives its outer coat of thick, 

 jelly-like substance, which swells up as soon as the ^g% is laid, 

 and serves to protect the egg during the cleavage and early 

 embryonic stages of development. 



4. TJie Secojid Polar Division. 



All the eggs taken from the lower part of the oviduct show 

 the fully formed second polar spindle lying at the periphery of 

 the Q.^g, just below the first polar body. It can be readily dis- 

 tinguished from the first polar spindle by its more slender shape 

 and more delicate fibers. The fibers of this spindle also con- 

 verge to distinct points, but there is absolutely no sign of a 

 centrosome, a radiation, or an accumulation of either protoplasm 

 or pigment at the spindle poles. The six groups of chromatin 

 loops are arranged at the equator with the angles of the loops 

 turned in, as they were in the first polar spindle (PI. XXX, 

 Fig. 34). The sister chromosomes, which have apparently been 

 fused, soon separate, so that, in a longitudinal section of the 

 spindle, there appear twelve pairs of dumb-bell-shaped chromo- 

 somes which again give the impression of being tetrad groups 

 (PI. XXX, Figs. 35, 36). In this case, however, each chromo- 

 some no longer has a double value, as it represents but one- 

 fourth of a chromatin ring. The chromosomes separate in 

 such a manner that one from each pair, i.e., twelve chromosomes, 

 goes into the second polar body. The second polar division 



