MR. SKEY ON MUSCULAR FIBRE, 
375 
and well defined as in the recent fibre, and I am informed by Mr. Owen that they 
remain perfectly unaltered in muscular fibre that has been immersed in spirit since 
the period of Mr. Hunter. 
With respect to their use Proschaska says, “Nil aliud sunt quain profundiora 
vestigia a vasis, nervis et filis cellulosis, fibram circumdantibus, et ejus vaginam per- 
reptantibus impressa,” and Fontana adopts this opinion of Proschaska, while the 
plates of the two authors bear but a very remote resemblance to each other. 
I conceive the arrangement of the transverse striee to be much too uniform to 
warrant the explanation of Proschaska and Fontana, for they are not grooves but 
positive elevations on the fibre. Nor are they invariably found on the muscular fibre 
of animal life, of which according to the views of Proschaska and Fontana they 
ought to be the invariable attendants, and with one exception never on that of 
organic life ; besides which, as I shall afterwards endeavour to prove, they are three 
or four times smaller than the globules of the blood themselves, and consequently 
cannot be destined to the transmission of blood vessels. They appear to hold some 
relation rather to the integrity of the fibre. 
In the Pharynx the size of the fibres varies from the -^y^th to the - 3 -y^-th of an inch 
in diameter, and here is exhibited the greatest variety in the circular striae. They 
are invariably large as the fibre is small, while the broader fibres, exceeding greatly 
the average diameter of 0 f an inch, exhibit the most delicate pencilling and as 
minute as the eye can detect. I have once observed them varying in size on the same 
fibre (Plate XVII. fig. 4.). 
Is it probable, therefore, that they are destined to the purpose of conveying vessels 
or nerves, or that they are mere cellular threads ? Throughout the general system of 
animal life, and except in the Pharynx, the circular striae are most prominent in the 
large and well-formed fibre, the completeness and integrity of which is its most cha- 
racteristic feature. 
If a portion of muscle, which has degenerated by disease and consequent inaction, 
be submitted to observation, it will exhibit the outline of the fibres without any trace 
of the striae or longitudinal filaments ; little, indeed, remains beyond the mere form 
of the fibre. I have examined the gastrocnemeus and soleus muscle of a person for 
many years bedridden, in which these muscles were wasted to a whitish mass, little 
exceeding in diameter that of their own tendons. 
The striae appear to bind together the united strands of the fibre, retaining them 
in position around the cylinder ; they are the woof to the warp of the longitudinal 
filaments, but instead of being interlaced with them they form circles around, and 
attached to the most prominent part of the longitudinal filaments to which they are 
intimately united. 
The Filaments or Longitudinal Striae. 
I have retained the name of fibre to that division of a fasciculus, which though ex- 
tremely minute, is apparent to ordinary vision. 
