66 H. E. JORDAN 
35. Sareostyle of elater, fixed in 95 per cent alcohol and stained with iron- 
hematoxylin, showing a greater degree of constriction and beading due to alco- 
holic dehydration. These fibrils almost invariably break at the level of the 
telophragmata. The constriction in the region of the Q-dises under these con- 
ditions would seem to indicate a greater degree of relative fluidity here than in 
the J-dises; and the bulging at the level of the telophragmata demonstrates a 
relatively great rigidity on the part of these membranes. 
36 Sarcostyle of elater, at later phase of contraction, showing, especially 
well at the upper end, the ultimate fibrillar elements (metafibrillae) of which 
the sarcostyle is composed. Fixed in 95 per cent alcohol, stained with iron- 
hematoxylin. X 1300. 
37 Sarcostyle of wasp’s wing muscle including three sarcomeres, in relaxed 
condition. The deeply staining Q-dise is unusually long for material fixed in 
alcohol, possibly due to a stretched condition of the fibril. 95 per cent alcohol 
fixation, iron-hematoxylin stain. X 2600. 
38 Sarcostyle of wasp’s wing muscle including four sarcomeres, in the relaxed 
condition, with unusually short Q-dises. 2600. 
39 Three sarcomeres at early stage in contraction. A very narrow H-dise 
bisects the unusually long Q-dises. X 2600. 
40 and 41 Successively later phases of contraction. XX 2600. 
42 Still later phase of contraction. Two early contraction bands appear 
toward the upper end of the sarcostyle, each composed of opposite halves of 
successive Q-dises fused about the telophragma. X 2600. 
43 Late phase of contraction, showing a stage in the reversal of striations. 
The H-dise of the earlier phase of contraction now forms the light stripe of the 
fibril. X 2600. 
44 Sarcostyle in full contraction, showing five (double) contraction bands. 
These fibers always break along the middle of a contraction band, that is, at 
the level of the telophragma. The faint stripes bisecting the space between 
successive contraction bands may be the mesophragmata. X 2600. 
45 Small area of transversely cut wing muscle of wasp. The wing-like 
processes of the sarcosomes are seen to encircle the sarcostyles. Above is shown 
a nucleus. Flemming’s fixation, iron-hematoxylin stain. X 1300. 
46 Sareostyle viewed on end, from a preparation according to Rollet’s 
method, showing ‘pores.’ These ‘pores’ are fixation artifacts. The dots among 
the pores represent the metafibrillae. x 1300. 
47 Transverse section of three sarcostyles of wasp, fixed in Flemming’s 
solution and stained with iron-hematoxylin, showing results of progressive 
destaining with the iron-alum solution. 
48 Seven sarcostyles and five sarcosomes from the wing muscle of the wasp, 
cut transversely. Flemming’s fixation, iron-hematoxylin stain. X 2500. 
