TETRAD AND EMBRYO-sac MITOSES 69 
Occasionally, however, the spindle is found to lie obliquely, and 
one or both ends may become connected with the ectoplasm.* 
In no case is a centrosome or centrosphere to be found. I 
have been able to follow finely-pointed spindles to their extreme 
end without finding any trace of the body which can without.doubt 
be regarded as such. Ina recent paper by Meves and von Korff 
on the Myriopoda, ۲ the ‘‘centralkérper” are described as lying 
very near to the periphery of the cell, and are apparently not di- 
rectly in connection with the spindle. The latter, however, is not 
pointed, while its fibers nevertheless are directed toward the kinetic 
centers, 
Thus is formed a condition in which the centrosomes are con- 
siderably removed but still in control of the spindle ends. 
In spite of the obvious difference in the character of the spindle 
itself, I was led to examine carefully every part of the cytoplasm 
lying in or near the spindle axis, but with a negative result. 
The multipolar origin of the spindle in certain plant cells has 
' been for some time regarded by the majority of botanists as speak- 
ing against the existence of the centrosome in plants in which the 
spindle has such an origin. Although a contrary view has been 
held by Guignard f it would still appear that the former position 
is more consonant with the facts as they are at present understood. 
For we would expect in such cases either as many centrosomes 
as spindle ends, or two whose influence would be exerted over the 
whole kinoplasmic figure (archoplasm). The former is shown to 
be the case in the development of the curious worm-shaped sper- 
matozoon in Paludina, an account of which has lately appeared. $ 
According to Meves the centrosphere of the primary spermatocyte 
contains a number of central granules which act as a unit. In 
the second mitosis the granules (Centralkórperkórner) separate 
and take a position in the periphery of the cell, and from these as 
centers are formed a number of half or partial spindles. The re- 
sult is a picture which resembles in its later development to some 
* Ectoplasm is here used to signify the ** Hautschicht ”of the Germans. 
t Meves, Fr , and von Korff, K. ** Zur Kenntniss der Zelltheilung bei ENSEM 
Archiv mik. Anat. und Entwickelungsgeschichte, 57 : 481-486. fl. 27. 1901 
I Centrosomes in Plants. Bot. Gaz. 15 : 15 1999. 
¿Meves, Fr. Ueber die sog. wurmfórmigen Samenfäden von Paludina und über 
ihre Eo Viele: Mitth. Verein Schles.-Holst. Aerzte. 10: No. 1 
