Intelligence and Miscellaneous Articles. 345 



Dr. Barry compares the appearance of the vegetable " dotted duct," 

 in its several stages, with that of objects found in mould, in the 

 cornea, in the crj'stalHne lens, and in voluntary muscle ; all of which 

 are produced by associations of minute spiral threads. The distri- 

 bution of the remarkable filaments above described is so universal, 

 that they are found in silk, in the incipient feather, in hair, in the 

 feather-like objects from the wing of the butterfly and gnat, and in 

 the spider's web. 



Dr. Bariy informs us that he has had the opportunity of showing 

 to several physiologists the principal appearances described in his 

 memoir on fibre. And Professor Owen permits him to state, that 

 he has exhibited to him spirals in voluntary muscle, — muscular 

 " tibrillse " having a flat, grooved, and compound form,— the fila- 

 mentous structure of the " white substance in nervous fibre," — the 

 vegetable spiral becoming double by division, — a coiled filament 

 within red blood-discs, — and the incipient unwinding of the coil in 

 coagulating blood. 



FURTHER REMARKS ON FIBRE. BY MARTIN BARRY, M.D. 



Dr. Barry examined the following objects, from two of the Mol- 

 lusca, at the desire of Professor Owen, who dissected them out for 

 the purpose : namely, from the Oyster, the branchial ganglion, and the 

 branch connecting it with the labial ganglion ; from the Loliyo, the 

 optic and brachial nerves. In all of these Professor Owen recog- 

 nised filaments ("fibres") having the same remarkable appearance 

 as those which Dr. Barry had previously shown to him in muscle. 



On a subsequent occasion — several physiologists being present, 

 one of whom was Professor Owen — there were seen muscular 

 " fibrillae," not only flat, grooved, and compound, but separated at 

 the end into their single and simply spiral threads, — the really ulti- 

 mate threads of muscle. In this instance chromic acid was substi- 

 tuted for the reagent above- mentioned (p. 344.) as usually employed 

 by Dr. Barry in these researches : and for the examination of muscle 

 he now finds the chromic acid to be even preferable thereto*. 



To find the muscular " fibrillae " of a size proper for examination, 

 and so loosely held together that they may be separated with ease, 

 the heart of a fish or reptile should be employed. Dr. Barry has 

 used the heart of various fishes, as well as that of the turtle, newt, 

 and frog — and chiefly the frrg. 



To find those states of voluntary muscle in which the transverse 

 strite are produced by the windings of comparatively large interlaced 

 sjjiral filaments (see abstract of the postscript to Dr. Barry's paper 

 " On Fibre," p. 3-24), he recommends muscle from the tail of the very 

 minute tadpole — when this larva is only 4 or 5 lines in length (as at 

 the present season) — or muscle from the leg of a boiled lobster, as 

 being very easily obtained. In these states of muscle, the interla- 

 cing spirals are seen to dip inwards, towards the centre of the fasci- 

 culus, in a manner that may be rej /resented by making the half- 

 bent fingers of the two hands to alternate with one another, and then 

 viewing them on the extensor side. 



• We are indebted to Dr. Flannover for bringing into notice the use of 

 the chromic aciJ for sucli purposes. 



Piiil. Mag. S. 3. Vol. 20. No. 131. April 1842. 2 A 



