256 PROCEEDINGS OP THE AMERICAN ACADEMY 



But though most of the patterns can be explained in this manner, 

 there nuiy exist otlier factors still unknown explaining the opposite 

 patterns. Tlie explanation given can be considered as admissible as 

 long as the number opposite to it is a comparatively small one. 



The pattern on the wings and elytra cannot, of course, be the pro- 

 duct of action near or along the muscles, as these limbs are unprovided 

 with them internally. JBut it seems probable that there the sudden 

 rush of blood and air by the accelerated circulation and respiration 

 during the act of transformation produces the same effect. At least 

 some patterns, the origin of which would be inexplicable, could be 

 understood bj it. 



If a stream or jet of blood passing through the narrow base of the 

 wingbag should meet within its centre a small obstacle, the pre- 

 viously straight stream would take the form of a funnel. Should 

 this obstacle be a kind of ring, the funnel shape would be retained 

 by the stream, but its central portion would pass undivided through 

 the ring, and upon meeting another obstacle would produce a second 

 funnel. Therefore there may be two or more funnels, one within the 

 other, and a section of them will be circular or elliptical according 

 to the angle at which they reach the inner surface of the wing. A cu- 

 rious fact seems favorably to support my suggestion. Nearly every 

 larger ring or eye-spot of the wings shows a white interruption or 

 spot in some place. Now as it is impossible that any obstacle, such as 

 mentioned before, can be entirely free and isolated in the stream, we 

 must presume that it is somewhere connected with the interior of the 

 body, and is perhaps produced by some prominent ridge or corner, 

 and then the funnel or the ring must be interrupted in some place by 

 this connection. If it is so, this place will not be oxidated (colorless), 

 and will correspond to the white spot mentioned before. 



Such patterns of the elytra and wings have to be performed at the 

 time when the wing is still an open bag, and before the transforma- 

 tion. There is still another circumstance which explains some pat- 

 terns. The walls of the bag which will be later a wing or elytron, 

 are very suddenly enlarged and strongly dilated during the act of 

 transformation. Therefore small rudimentary patterns in the bag 

 will be altered and enlarged by the same proceedings. I know that 

 many patterns of Lepidopterous wings can be easily explained in this 

 way. All the wavy lines and similar marks belong to these patterns. 

 As the ribs or veins of the wings seem to grow faster in transforma- 

 tion than the membrane between them, the wavy shape of the lines 



