MUSCLE. 137 
each primitive muscular fasciculus is a secondary cell, formed 
by the coalescence of primary round cells, each furnished with 
a nucleus, and which were arranged together in a row. After 
the coalescence of the contiguous portions of the cell-walls has 
taken place, an absorption of the septa remaining between the 
cavities of the two neighbouring primary cells must commence, 
since no such septa can be perceived within the secondary cell 
at a later period. If the little transverse striz, by which the 
cavity of the fibres is sometimes divided, be actually nuclei 
placed transversely upon their edges, they are probably such 
as lay upon that part of the wall of the cells which was ab- 
sorbed. It seems that the coalescence of the cells, however, 
is not sufficiently complete to prevent a separation taking 
place more readily at the points of junction than elsewhere, 
and on this the phenomena of the artificial division of muscle 
before mentioned probably depend.’ 
When I made my first communication upon the formation 
of the primitive fasciculi of muscles by the coalescence of cells 
(Froriep’s Notizen, No. 103), the only corresponding instances 
known to exist among vegetable cells were those of the spiral 
and lactiferous vessels. The interest attached to the subject 
has very much increased since Meyen’s discovery of a much 
more striking analogy in the cells of the liber or inner bark 
—(bastzellen). (Wiegmann’s Archiv, 1838, p. 297.) He found 
that these long-extended cells, when boiled in hydrochloric 
acid, fell into small particles of nearly equal length; and 
investigation into the development of the cells of the liber in 
buds showed, that m the early period a corresponding quantity 
of distimct, somewhat longitudinally extended, prismatic, pa- 
renchymal cells are present, which are placed with their 
extremities accurately arranged one upon another, that they 
unite together at those parts, and that their septa are after- 
wards absorbed. 
The secondary muscle-cell passes subsequently through all 
the changes incident to a simple cell. Its wall is at first thin, 
' It might be important to examine whether the zigzag plications of muscles, 
during contraction, have not perhaps some connexion with the length to which the 
portion of a muscular fibre generated from one single cell has become expanded, so 
that probably the angle of each flexion coincides with the point of junction of two 
cells. 
