OBSERVATIONS ON STRIPED AND UNSTRIPED MUSCLE. 101 



Fig. 9. Muscle-cell from Kat's heart, showing network. Usual gold 

 method. Zeiss, D obj. 



Fig. 10. Muscle-fibre from Frog's heart. (Osmic acid, 1 per cent., 

 half an hour.) fa imm. obj. 



Fig. 11. Network from heart-muscle of Bird. (5 per cent, acetic 

 acid fifteen minutes, gold thirty minutes, formic acid 

 twenty -four hours.) fa imm. obj. 



Fig. 1 2. Portion of unstriped muscle-cell from mesentery of Newt, 

 showing intranuclear network and its connection with the 

 fibrils of the cell. (5 per cent. amm. chromate twenty- 

 four hours ; logwood.) fa imm. obj. 



Fig. 13. Part of fibre from bladder of Salamander, showing fibrils. 

 Usual gold method. fa imm. obj. 



Fig. 14a. Muscle-fibre of Dytiscus, stimulated with alcohol vapour. 

 Portion a relaxed, b. Contracted, fa obj. 



Fig. lib. Network of relaxed portion. ^ imm. obj. 



Fig. 14c. Network of contracted portion, fa imm. obj. 



Fig. 15. Diagram of a muscle-fibre, showing change in network 

 during contraction. 



Fig. 16. Diagram of the intracellular network of striped muscle. 

 a. The transverse networks, b. The longitudinal bars of 

 the network. (Copied from Melland, loc. cit., Diag. 1.) 



Fig. 17. Portion of network on a larger scale. (Copied from Mel- 

 land, loc. cit., Diag. 2.) 



Fig. 18. Portion of muscle-fibre of Dytiscus, showing the network 

 very plainly. One of the transverse networks is split off, 

 and some of the longitudinal bars are shown broken off. 

 (Copied from Melland, loc. cit., Fig. 6.) 



Fig. 1 9. Hypothetical diagram of the termination of nerve in muscle- 

 fibre and the connection with the network; based on 

 views discussed in the paper. S. Sheath of Schwann, 

 continuous with sarcolemma. n. Axis-cylinder branching 

 and connected with muscle-corpuscles, m. Muscle-cor- 

 puscles connected with transverse networks. 



