HarleYj on Cutaneous Respiration. 
153 
it differs from it in the absence of nuclei^ and the very slight 
tendency to split up into spindleform bodies. The bands 
cannot be said to consist of fibrous tissue,, for they are very 
broad, and not separable into fibrils. Neither are they made 
up of the ordinary areolar tissue^ for they swell but very 
slightly on the addition of acetic acid. They greatly re- 
semble the elastic fibres in cartilage, and behave towards 
reagents in a somewhat similar manner. That they are 
elastic one cannot doubt ; for the skin^ of which they com- 
pose the greater part, is very elastic. If Professor Ellis's 
views regarding the structure of non-striated muscles be 
correct^ namely, that they are not made out of nucleated 
cells, as KoUiker supposed^ but are formed of bundles of 
fibrils or threads, with nuclei distributed here and there on 
their surface^ I should incline to the opinion that these bands 
are a peculiar form of non-striated muscular fibre; and I 
should consider their not splitting into cells, each containing 
a separate nucleus, additional evidence in favour of Professor 
Ellis's opinion. Without wishing to enter into the discussion 
lately raised by Professors Ellis and Thomson, and Mr. Lister, 
regarding the structure of non-striated muscular fibre, I 
may say that the whole subject appears to me to resolve 
itself into the single question, " Are the bodies described 
by Professor Kolliker and his followers as cells, cells in 
the ordinary acceptation of the word?" That is to say, 
do they consist of a cell- wall and distinct contents, with a 
nucleus in the centre ? or, are they, as Professor Ellis thinks, 
fibres made up of a number of threads or fibrillse ? As it 
happens that the smooth muscles occurring in the difi'erent 
organs of the body, although they bear a general resemblance 
to each other, yet difier as to structure in several particulars, 
it must be borne in mind that the following remarks are 
only applicable to the muscle described. In the intestine of 
the cat, kept a day or two in a weak solution of nitric acid, 
the cells very often present a corkscrew appearance 
throughout their whole extent, but more particularly at 
their ends. When pressed, they take on the wavy outline 
spoken of by Kolliker. Other " cells," more stretched, have 
a remarkable jointed appearance, like a bamboo cane, and 
when examined with a good lens of high power, the spaces 
between the joints are seen to have a linear arrangement, 
which Mr. Ellis thinks is produced by the fibrillse. Be that 
as it may, one thing appears to me certain, that the spindle- 
shaped bodies, described by Kolliker as cells, ay-e solids for 
they may be cut across or torn longitudinally without any 
contents protruding or flowing out. The torn ends and sides 
