82 C. F. MARSHALL. 



for the sake of distinctness, ith obj. Acetic acid, osmic acid, and gold 

 chloride. 



Fig. 2. — Portion of another fibre, with transverse networks connected with 

 two rows of muscle-corpuscles. -^qUi immersion obj. Same method. 



Fig. 3. — Three isolated muscle-corpuscles of Dytiscus muscle, with trans- 

 verse networks attached. j\fth immersion obj. Same method. 



Fig. 4. — Muscle-corpuscle of Dytiscus, with portion of transverse network 

 connected with it. Transverse view. Gold preparation, ^^^th immersion obj. 



Fig. 5. — Muscle-fibre of dragon-fly, showing two muscle-corpuscles with 

 their intra-nuclear network. Some of the transverse networks are seen to 

 be connected with the intra-nuclear network of the upper corpuscle, ^oth 

 immersion obj. Acetic acid, osmic acid, and gold chloride. 



Fig. 6. — Muscle-corpuscle of crayfish, with portion of the muscle network 

 apparently connected with its intra-nuclear network. J^th immersion obj. 



Figs. 7 and 8. — Developing muscle-fibres of trout, showing striation. ti. 

 Nucleus. Y^th immersion obj. Acetic acid 2 per cent., a few seconds ; gold 

 chloride 1 per cent., fifteen minutes ; formic acid 25 per cent., thirty minutes 

 in warm chamber. 



Fig. 9. — Portion of the striated part of one of the above fibres, showing 

 the network and the darkly stained bodies in its meshes. Jgtii immersion obj. 



Fig. 10. — More fully developed fibre of trout, n. Nucleus, y'^gth im- 

 mersion obj. 



Fig. 11. — Muscle-fibre of Dytiscus, with a portion of nerve-ending appa- 

 rently connected with the longitudinal bars of the network, joih imm. obj. 

 Mays' method. 



Fig. 12. — Muscle of crayfish, showing a "streak" of nerve-ending appa- 

 rently connected with the longitudinal bars of the network. y\jth imm, obj. 

 Retzius' method. 



Figs. 13 and 14. — Diagrams comparing the view of Uollett and others 

 with the network. In Fig. 13 the structure, according to Rollett, is marked 

 in full lines, and the network marked in dotted lines. In Fig. 14 the thick 

 segments of RoUett's muscle-columns are shown by dotted lines in the 

 meshes of the network, ti. Network, s. Muscle-columns, ff. Granules. 



Fig. 15. — Portion of muscle-fibre of Dytiscus, showing network very 

 plainly. One of the transverse networks is split off, and some of the longi- 

 tudinal bars are shown broken off. (Copied from Melland, loc. cit., fig. 6.) 



[Note. — In figure 13 the lines connecting the thick parts of llollett's 

 muselc-columns should be much thicker. They represent the thin segments 

 of the columns.] 



