CHROMOSOMES AND MITOCHONDRIA 281 



small, transparent, slightly refringent granules of a 

 pale gray tint, either homogeneous or else vesicular 

 with fluid contents and a thin, denser, refringent 

 periphery. Rod-like mitochondria were likewise 

 observed by Montgomery (1911) in the living male 

 germ cells of Euschistus (Fig. 78, A-B) which had 

 been teased out in Ringer's solution; and this in- 



FIG. 78. Division of mitochondria. A B. Mitochondrial rods divid- 

 ing during first maturation division in Euschistus. C. Stages in 

 division of mitochondria! body in Hydrometra. D. Simultaneous 

 division of micronucleus and mitochondria in Carchesium (in vivo). 

 (A-B, from Montgomery, 1911; C, from Wilke, 1913; D, from 

 Faure-Fremiet, 1910.) 



vestigator concluded that in preserved material "we 

 have been working with images that are very close 

 to the living. ..." More recently Lewis and 

 Lewis (1914) have made careful studies of mitochon- 

 dria in living cells from chick embryos. Granules 

 were here seen "to fuse together into rods or chains, 

 and these to elongate into threads, which in turn 

 anastomose with each other and may unite into a 

 complicated network, which in turn may again 

 break down into threads, rods, loops, and rings." 

 Even more remarkable are the movements within the 



