252 OR. 6. THIN. 



drical thread of definite and uniform size and appearance, 

 and in gold preparations exposed to light in acidulated 

 water an intermediate darkly -stained substance was seen 

 to adhere to the fibrilla. 



Muscular fibres of the frog were sealed up on an object- 

 glass in mixtures of half per cent, solution of chloride of 

 gold and acetic acid in varying proportions, and the changes 

 which took place observed daily. Amongst these changes 

 ihere were two distinct kinds of appearance seen. In some 

 instances the mass composing the muscular fibre became for 

 the most part nearly invisible, and in it parallel rows of spindle 

 elements became prominent. These consisted of a longi- 

 tudinal series of oval swellings connected by a round 

 well-marked fibre. The independence of these spindie 

 elements as regards the substance of the fibre was estab- 

 lished by their being often seen to project beyond it. In 

 another set of preparations an immense number of rounded 

 discs were scattered over the field, singly and combined in 

 circular groups. These came from the end of the fibre, 

 which was seen to be full of them, the appearance being 

 likened to the open end of the cornucopia. The fibre, 

 which formed the subject of illustration in the paper 

 referred to, Avhen looked at some weeks later was observed 

 to have been divided into these small discs throughout, the 

 form of the fibre, however, being retained except at the ends. 



When the muscular fibes of the frog were deeply stained 

 by the action of chloride of gold and subsequent exposure to 

 light in acidulated water, and finally kept for six to twenty-four 

 hours at the temperature of 100° Fahr.in strong acetic acid, the 

 muscle substance could be manipulated by needles, and 

 there could be isolated from it portions of a network more or 

 less large. This network was composed of exceedingly fine 

 fibres, and its meshes accurately corresponded to Cohnheim's 

 fields. The isolation and the independence of the minute 

 fibres composing it were complete. In the central points of 

 the meshes a minute spot had been stained by the gold so- 

 lution, and scattered over the network were single larger 

 stained patches from which fibres radiated that anastomosed 

 with those of the network. None of the portions isolated 

 were larger than the area of a transverse section. The deeply 

 stained larger patches had the form and tint of the branched 

 cells of connective tissues when these are similarly treated. In 

 fibres treated by gold solution and acidulated water I had 

 isolated elongated narrow nucleated cells lying amongst the 

 fibrillae. In fibres which had been two or three da}s in gold 

 solution, then mounted in a mixture of gold solution and 



