254 
George Arnold 
nature as the chondriosome, since the latter is a permanent cell organ, 
present in some form or other during the whole life of the cell. 
But the ergastoplasmic bodies are so similar to ehondriosomes in their 
structure and position in the cell, that it is difficnlt to escape the con- 
clusion that the two things are identical, and that the apparently transitory 
nature of the former is due to the use of unsuitable fixatives and stains. 
It will be seen later on, that there are periods when the ehondriosomes 
of the pancreatic cells are also not easily brought into evidence, even in 
tissue which has been fixed in a fluid suitable for the proper demonstra- 
tion of the ehondriosomes. And in this connection it is to be remarked 
that even Prenant, hitherto a strong upholder of the individuality of 
the ergastoplasm, is constrained to admit, that that view is no longer 
tenable in its entirety. He says, “L’ergastoplasm en effet, coincidera de 
plus en plus avec la mitoc-hondrie: tous deux ne sont sans doute que deux 
aspects differents que prend une meme formation soumise ä des techniques 
differentes. Lequel de ces aspects est le plus fidele, le plus voisin de la 
realite? 
Si l’ergastoplasme est pour moi amicus et meme filius adoptivus, 
la verite m’est encore plus chere, et je dois reconnaitre que l’image mito- 
chondriale semble plus vraie que Image ergastoplasmique, parcequ’elle 
se voit ä l’etat vivant et que sur les pieces fixees et colorees eile est aussi 
plus precise. : ’ 
During the last three years a large amount of research has been pub- 
iished which goes far in Support of the conc-lusions arrived at by Meves. 
Especially noteworthy are, a paper by Duesberg (1910 i) dealing 
with the derivation of the myofibrils from the ehondriosomes of the em- 
bryonic myoblasts; the work of Hoven (1910) on the origin of the neuro- 
fibrils, and of Firket (1911) on the origin of the epi dermal fibrils, and a 
paper by Meves himself on the connective tissue fibrils. 
In each case the author has been able to trace the evolution of tliose 
structures from the ehondriosomes of the embrvonic cells. 
These four papers have been especially emphasized, because in them 
the continuity of the ehondriosomal elements has been demonstrated 
from the embryonic to the adult tissue, so thatwe are in a position to assert 
that the myofibrils, the neurofibrils, the epidermal fibrils and the con- 
nective tissue fibrils are directly derived from ehondriosomes or are their 
metamorphosed products. 
In c-ourse of time, no doubt, the fate of the embryonic chondriosome 
will be ascertained in the case of all the tisäues and organs of the adult 
animal, but at present we are forcedtorely chieflyon the stainingreactionto 
