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Woodward ('• Ent.," 1896, p. 334) records hind legs of Nemeophila 

 planfaginis replaced by miniature wings ; no further details are given. 



A remarkable specimen is described by M. Clement (" Bull. Ent. 

 Soc. Fr.," 1898, p. 268) of a specimen o^ Ali/nas ti/ice, which presented 

 the caudal horn in the pupal and imaginal states. Details of these 

 structures are not afforded, but sufficient is reported in text and 

 tigure to make it fairly certain that these were respectively pupal 

 and imaginal structures, and not a mere retention of an actual larval 

 structure, as is the case in the frequently noted instances of pupae 

 and imagines with larval heads. Nor, again, is it related to the 

 frequent instances of pupje of Sphingidce showing prominences in the 

 positions of the larval horn, or of the prolegs, or claspers. 



In 1886 Frivaldszky recorded a longicorn {Cera/nbyx scopoiti) vi'ith. 

 both antennae on one side of the head. I have not seen the original 

 record, so cannot say how far it has anything in common with the 

 following. 



McLachlan's remarkable case of a dragonfly having two fore-wings 

 on one side and only the hind-wing on the other ("E. M. M.," 

 1896, p. 83) ought to repay further study if the specimen is avail- 

 able. One surmises that, as a result of some injury in an early 

 larval instar, the imaginal disc of the right fore-wing was detached 

 from its natural connections, and dislocated to the opposite side in 

 apposition with the imaginal disc of the wing of that side. That so 

 elaborate a surgical operation should happen to take place by the 

 attack of some larva of a water-beetle or other predaceous enemy 

 with which ponds and streams abound, and from which the dragon- 

 fly just managed to escape with its life, is quite conceivable, though 

 survival after so severe a surgical operation must be very rare. It 

 would follow that it would illustrate also a quality of germinal 

 matter to which many circumstances point. 



This is, that germinal material is not ear-marked by its own 

 •qualities and structure, but by its position ; a certain portion of 

 germinal matter either in the fully segmented egg or later might 

 develop into, say, a right wing, or a left leg, or any other structure, 

 but having happened to be situated in relation to other germinal 

 masses in the place where, say, a right wing has to appear, its 

 development occurs accordingly. In the case before us, the 

 imaginal disc of the right tore-wing was ear-marked to be a wing, 

 but its change of position occurred in time for it to develop into a 

 left instead of a right wing. McLachlan's account implies that it is 

 a left wing, and not a right one on the left side, but a close examina- 

 tion of the specimen is desirable to decide this and other points. 



It is remarkable how frequent this species of malformation is in 

 the Anthrocerids {Zygiena, Chalcosia), the recorded instances being 

 vastly in excess of the proportion due to their numbers, wings 

 growing instead of legs, hind-wings replaced by fore-wings, etc. The 

 group ought to be worth a careful examination by way of experiments 

 on the larva;. 



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