STRIPED MUSCLE OF WASP 41 
And the beading of the sarcostyle in hypotonic solutions is de- 
pendent upon the’ presence of the telophragma and its attach- 
ment to a peripheral layer with the properties of a membrane. 
The same fact is illustrated in figures 46 and 47. Figure 47 shows 
in transverse sections three successive stages in the progressive 
destaining after application of the iron-hematoxylin stain. The 
late phase shows a central deeply straining granule (fibril?) and 
a delicate peripheral membrane. 
VI. DISCUSSION 
a. Telophragma and mesophragma 
In the fundamental morphology of striped muscle there is 
perhaps no element more uniform and definite than the telo- 
phragma. Thulin?’ recently published a paper in which he 
claims that a telophragma does not occur in the wing muscles of 
Coleoptera, Diptera, and Hymenoptera. His illustrations make 
it clear that he is referring to the intersarcostylic portion of the 
telophragma, for the intrasarcostylic representative is plainly 
indicated. 'Thulin’s sole evidence in support of his claim that 
these muscles lack a telophragma is his observations on sectioned 
material. His illustrations show that the material suffered con- 
siderable distortion and fragmentation by his technic, as indi- 
cated chiefly by the relatively wide spaces between adjacent 
sarcostyles. I have examined specimens of fresh and fixed wing 
muscle of representatives of each of these groups of insects. In 
fresh specimens teased in Ringer’s solution groups of closely 
adherent sarcostyles occur in which the telophragmata lie at the 
same transverse levels over as many as from six to ten adjacent 
sarcostyles. The slight resistance offered against dividing a 
group of sarcostyles by teasing is additional evidence that a 
connecting telophragma exists. 
From a study of well-fixed tissues similar evidence accrues. 
Examination of such areas as represented in figure 21 can leave 
no doubt that the telophragmata of the sarcostyles span also the 
extremely narrow intersarcostylic spaces and hold the several 
discs of the sarcostyles in uniform horizontal alignment. This 
