OF MUTANT CHARACTERS. 



155 



BLISTERED (b,). 



(Text-figure 74.) 



ORIGIN AND DESCRIPTION OF BLISTERED. 



The mutation ''blistered"^ was found by Bridges (November 16, 

 1911) in a mixed stock of rudimentary and normal (culture A23) as a 



Costa, or marginal vdn 



ongiiudinal vein 



Text-figure 74. — Blistered wing and venation. 74a shows a pair of wings with the l)end in the 

 fourth longitudinal vein, and extra veins. 746 shows the plexus near the end of the fifth 

 longitudinal vein. 74c shows for comparison a normal wing with the standard terminology 

 for venation and for the cells of the wing. It is probable that 74c is on a larger scale than 

 74a and 746, though the blistered wing is characteristically smaller than normal. 



not-rudimentary female which had in each wing a small vesicle in the 

 region of the fifth longitudinal vein just beyond its junction with the 

 posterior cross- vein. This female was bred to a wild-type brother and 



'MacDowell ('15)published bristle counts on this stock under its earlier name of "half-balloon." 



