236 ; M. M. Metcatr 
shaped pseudopodia. In some dumbbell-shaped nuclei one sees, in 
one end, the chromosomes already thus fragmented or fused, while 
in the other end of the same nucleus the eight chromosomes are 
compact and distinct (Fig. 34, Pl. XVI; 63, Pl. XIX). 
The chromosomes, even in their most compact condition, give 
off numerous threads which connect with the general chromatic net- 
work. Unless the staining is satisfactory the threads themselves 
are sometimes difficult to see, but one rarely fails to notice upon 
the surface of the chromosomes the pointed protrusions with which 
the threads connect. 
The chromosomes differ in size and form and in the number of 
eranules they contain. After much study I must confess that I am 
not sure whether these differences are constant. The granules are 
so small and, especially in this stage, so difficult to see, that the 
margin of error in the count in a single chromosome is greater than 
the difference betwen the numbers in different chromosomes. In the 
first attempts to count in different nuclei the granules in the chromo- 
some which is the first to divide during the telophase, the numbers 
so nearly agreed as to give hope that evidence from this source 
would prove valuable, but further study has rendered the whole 
matter so doubtful that it is best to say nothing further of it. 
Similarly, after prolonged study of the form and size of the chromo- 
somes, I feel that it would be unsafe to express an opinion as to 
the constancy of these characters. It is true that there is usually 
a remarkable degree of resemblance between the chromosomes of 
the two ends of the same nucleus in their size and form and in 
the time and manner of their division or fusion in the early telo- 
phase. It is also true that one finds nuclei in different animals 
whose chromosomes show equally remarkable resemblance in these 
regards. Yet the whole series of phenomena is so often confused 
by the early appearance of division or fusion in the telophase and 
the precocious appearance of the characteristic differences between 
the anterior and posterior nuclei, that is seems unsafe to conclude 
from the resemblance referred to that the chromosomes have con- 
stant and characteristic differences from one another. I incline to 
that belief, but cannot quite convince myself. It would be easy to 
give rather convincing drawings, if only the most favorable nuclei 
were selected, but the study of hundreds of nuclei shows the 
conditions to be too various for satisfactory solution of the 
question. 
