IIWOLIJNTAET MUSCrLAE TISSUE OF THE UEINAEY BLADDEE. • 473 
nuclei of cells of Professor Kollikee) should be examined without acetic acid, or with 
only a very weak mixture of it and water, as when the acid is strong it destroys the 
characters of the object under the microscope*. These bodies (Plate XXVII. fig. 4) have 
the same general form, position on the fibres, and appearance as the corresponding bodies 
in voluntary muscle, and from each pointed end a faint line of granules may be often 
traced if weak acid has been used ; but their contents are more coarsely granular, and 
they are somewhat larger and better marked, measuring across from x i - .o ' oo ^^ 4 
of an inch, and along from j^ol^h to 4 ^ 6 ^^ inch. 
The number of the corpuscles on a single involuntary fibre of the bladder will depend 
on the length of the fibre, and their distance apart is greater than in the voluntary 
muscle. There is not any bulging of the fibre opposite the seat of the granular bodies 
(see Plate XXVII. fig. 4 a). On account of the softness of the muscular fibres and 
their frequent interweaving, a single fibre can be separated far enough from its fellows 
to show more than one corpuscle on it only rarely, and with considerable difficulty. 
With care, however, I have succeeded several times in detaching a piece of a fibre long 
enough to have two corpuscles, but only once, as in fig. 4 a, a fragment of a length 
sufficient to possess three corpuscles. 
The distance of the corpuscles from one another varies in the same fibre, as well as in 
different fibres. In the fibre with three large corpuscles (fig. 4 a), the middle one is 
-^^rd of an inch from one corpuscle, and 3 jo^h of an inch from the other. In five other 
fibres, each with two large corpuscles, of which measurements were taken, in no two was 
the interval the same, for it varied from to -^rd of an inch, but the average was 
y^th of an inch. 
Some small and imperfect corpuscles, as in fig. 4 a, are often seen betAveen the larger 
and more complete bodies ; and occasionally two larger ones are found near together, as 
if one was cleft in two. 
The measurements above given of the distance of the corpuscles from each other, were 
made on the fibres of a bladder that was very much contracted, of which fig. I, Plate 
XXVI. is a representation drawn of the natural size ; and it is therefore to be inferred 
that the distance would be increased in fibres in an uncontracted state, or lengthened in 
the distended condition of that viscus. Possibly, too, my seeing two and three corpuscles 
on a fibre may be due to the approximation of those bodies by the shortening of the 
intercorpuscular spaces in the contracted fibres. In this same small, but very healthy- 
looking and muscular bladder, some of the fibres presented a coarse granulous appear- 
ance, as in fig. 5, Plate XXVII., either through the whole length of the field of the micro- 
scope, or only at intervals : this condition was very like the granulous state often seen 
in voluntary muscular fibre. 
* Little knowledge of tliese bodies or of the fibres can be obtained by adding acid to a mass of the 
muscular substance, for the acid takes away all indication of the separateness of the fibres, and allows 
underlying corpuscles to appear through the superficial and transparent tissue. 
