DR. MARTIN BARRY ON THE CORPUSCLES OF THE BLOOD. 
605 
fig. 17 . be compared with y of fig. 18., taken from that author, a further correspond- 
ence will be observed. But it is not needful to refer to the observations of others, 
since the objects figured by myself ivere obviously muscular fibres (the future fasciculi) 
in the earliest stages of formation. There is therefore, it appears, a direct transition 
of blood-discs into the elementary parts of muscle. 
35. My observations have not extended farther than the condition yy of fig. 17- — 
for they were almost entirely incidental so that I am unable to state the mode of 
origin of the fibrillee within the cylinder. But certain facts communicated in my 
Third Series of Researches in Embryology, may perhaps be applicable here. 
36. It was there shown that a nucleus, after passing to the centre of a cell, resolves 
itself into the foundations of new cells. I would suggest that the nucleus may 
thus be the source of that “secondary deposit” described by Valentin and Schwann 
as thickening the membrane of the cylinder ; and am the more disposed to think this 
possible, from the observations of Schwann on the frequent metamorphosis of cells 
into fibres. The existence of the longitudinal fibrillee might perhaps be thus ex- 
plained, for Schwann remarks, that these fibrillee are formed out of the “secondary 
deposits.” — This suggestion corresponds to one offered in my last memoir on the 
possible mode of origin of spiral fibres and other secondary deposits in vegetable 
cells. 
37. It is not needful, however, that the central portion of a nucleus should leave 
the membrane of its cell, before the resolution of the free portion of such nucleus ; of 
which the germinal spot in its last stages affords a remarkable example'}-. I regard the 
pellucid objects in the cells Plate XXX. figs. 15. 17^? as occupying the place of the 
pellucid centres of the blood-corpuscles. 
38. In the cells fig. 16. no such pellucid objects were observed at the surface. 
But the cells presented a lighter central space, which I believe to have corresponded 
to the pellucid objects in question, — these having passed to that situation. And if 
the pellucid objects here seen are the seat of changes analogous to those presented 
by the mysterious centres of nuclei elsewhere §, it is not difficult to conceive the 
mode of origin of the “ secondary deposits” above referred to ||. The object (3(3 in 
fig. 17. presented a state apparently rather more advanced than those in fig. 16. The 
cells, however, had not coalesced. In yy of fig. 17. the coalescence had more or less 
completely taken place; and it is deserving of notice, that what in (3(3 appeared the 
separate pellucid objects in question, had in yy also coalesced, or seemed about to 
coalesce, to constitute the medullary portion of the cylinder. From the state of the 
fibre yy, it appears also that secondary deposits are in progress before the cylinder is 
fully formed. 
t “Third Series,” l. c., pars. 327, 328. J And also those in Plate XXIX. fig. 7, &c. 
§ “Third Series,” 1. c., pars. 375 to 395. 
H That the pellucid object in the altered blood-disc really undergoes these changes, is to be inferred from. 
Plate XXX. fig. 20. (par. 44.) 
