1894, ] z 
Attraction-Spheres and Centrosomes 
. 453 
defined, of a 
above S ehods cee the radiate structure. Any of th 
“proper care is Bacch: ba fairly good results with pl celled 
! ee ued plant cells, if 
iron-tannin-safrani it I prefer Hermann’s method or th 
ae : ule very small and u i 
sating owing appeanates lens, and generally a ye Sae 
€icountered in st iS rule, I think more dition Wiseats 
The killing ee : be these bodies in plants than in animals 
more displacement o not penetrate so readily, which causes 
Bie veretable sores distortion of the elements of the cell 
numbers of chromate moreover, are generally present large 
other such bodie atophores, starch grains, crystalloids and 
tification of Ta which myAy. greatly interfere with the iden 
tips which oS ter bodies as centrosomes. In the root 
of trouble; and led, I found the leucoplasts a constant source 
weful become apnea stains which might otherwise be very 
Bile color these “sie it because of the readiness with which 
Bilism is also - odies. The radiate structure of the cyto- 
| Bd cont: — less marked than in animal ceils. 
tamed material: somes and attraction-spheres in the following 
— I-it), in CET in the young root tips of A/um cepa L. (figs. 
BR the root +i 4g ae and the various stages of karyokinesis; 
ain ocr ‘par faba L. (fig. 15); in the root tips a 
dermis of the yg . (fig. 16); in the resting cells of the epi- 
18); and in th old bulb scales of Allium cepa L. (figs. 17 and 
of the ovary “e Asien of the anther (fig. 14) and the walls 
Se ithe onion r elium longifiorum Thunb. (figs. 12 and 13). 
 Rearly all the oot tips, I was able to trace them through 
in the youn stages of nuclear division (figs. 1-10) as well as 
Not trace eh ovaries of Lilium. In the other material I did 
i... m through the whole series, but in the Vicia and 
a them in several of the 
er he li 
oes bond then: vile Cae Mar cells of the lily 
“the * 
: Stage ect scales, where all the nuc 
a “Ueceeded in — there is no subsequent cell-division, I also 
~ Many cas emonstrating the existence 0 
ence fn 18). 
f aways two poe the bodies in resting 
8S in most somes, each with an attraction 
cases marked off from the surroun 
cells, there were 
-sphere, which 
ding cyto- 
