Reviews and Records in Anatomy and Physiology. 95 
thicker, and have varicosities at regular intervals. . . . My 
opinion is, that the transverse strie hold no essential, internal rela- 
tion to the contraction of the fibres, but are simply an expression 
of this last and of the organic elasticity of the fibrillee.”—( Mikro- 
skop. Anat., loc. cit. p. 263, 264.) 
This view which makes the fibrilla a homogeneous formation, 
and according to which the strie and disc-like structure, as usu- 
ally seen, are only resultant or secondary conditions, demands a 
special examination, considering the high authority of its source.* 
In the first place, we have not been successful in verifying the chief 
datum on which this opinion is founded ; we refer to the complete 
disappearance of the strie and the consequent perfectly smooth 
aspect of the fibrilla. If a small bit of muscle be taken fresh, 
ment receiv 
perhaps distorted striated appearance. 
Judging from our own experience, therefore, we should be 
disinclined to accept the opinion that fibrilla may be made to ap- 
pear free from strie,—on the other hand, we should attribute the 
alleged smoth aspect to the fact that probably sufficiently high 
aud excellent microscopic powers were not used in the examina- 
tlons. 
After this discussion of different and dissimilar opinions, we 
may revert to our primary leading question: What is the histo- 
logical composition of the muscular fibrilla? We shall be greatly 
aided in satisfactorily answering this question by referring to 
these formations as occurring under their simplest and most naked 
forms. If the muscles of some of the lower Crustacea, of Ar- 
ulus for instance, cr what is more convenient, of the thorax of 
the common house fly (Musca harpyia), be taken and examin- 
ed under the microscope with the usual care, the fibrille will be 
Seen very distinct, and separated from each other, at the same 
+ ae * 
Hassall advocates the same opinion based upon the allegation mtn the sie ry, 
be made entirely to disap by the action of acetic acid, (see 08. 4 
oxpisioaal Gee VOCE pp HETVs Bick thie ak tort Bhat tho Coed ORO eh 
rience, 
