a2, H. E. JORDAN 
clumps. The close connection of adjacent sarcostyles by the 
telophragmata apparently secures protection to a considerable 
degree against the swelling action of the hypotonic solution. 
Sarcostyles like A are only found isolated, and are in addition 
usually somewhat flattened out under the cover-slip. 
Fig. 7 (A, B, C, and D) Illustration of four sarcostyles of the wing muscle 
of Hydrophilus piceus (from Schaefer, after Ranvier). m, telophragma; h, 
median disc; e, dark disc (‘sarcous substance’); be, light dise (hyaline sub- 
stance’). Ranvier and Schaefer interprest A as ‘most contracted,’ and D as 
‘most extended.’ The fibrils are comparable to the sarcostyles of the wing 
muscle of wasp, bee, elater, and fly. As such the writer interprets C as a sarco- 
style in the relaxed condition; B as a sarcostyle in which the dark disc has become 
slightly swollen in consequence of the slight action of a hypotonic solution; A 
as a sarcostyle which has become swollen and beaded, and in consequence 
shortened (that is, artificially contracted) in consequence of the prolonged action 
of a hypotonic solution, and sarcostyle D as one in midphase of contraction upon 
which has perhaps been superposed a stretched condition. 
Schaefer?’ cites also Ranvier’s illustrations of the wing muscle 
sarcostyle of the water beetle, Hydrophilus piceus (fig. 7), in 
support of his interpretation of the wasp’s wing-muscle sarcostyle. 
Ranvier likewise considers the shortened beaded fiber (A) as 
contracted. Reference to Ranvier’s original article only gives 
the information that he studied these sarcostyles in the body 
fluid of the insect, in white of egg, in picrocarminate of ammonia 
and in a 2 per cent osmic-acid solution. He does not specify 
the particular fluid employed in the case of the muscle from 
which the illustration was drawn. Atleast two of these solutions 
are hypotonic to the living sarcoplasm. According to our inter- 
