Lindsley & Grell, 1972, pp. 45-46
discoverer: Bridges, 19l27.
references: Bridges and Morgan, 1923, Carnegie Inst. Wash. Publ. No. 327: 225 (fig.). Morgan, Bridges, and Sturtevant, 1925, Bibliog. Genet. 2: 214 (fig.), 219. Lewis, 1951, Cold Spring Harbor Symp. Quant. Biol. 16: 159-74 (fig.). 1955, Am. Naturalist 89: 73-89. 1963, Am. Zoologist 3: 33-56 (fig.).
phenotype: Posterior portion of metathorax becomes mesothoracic; anterior metathorax unaffected. Enlarged metathoracic postnotum forms two wedges of tissue, devoid of hairs and bristles, meeting at the mid-dorsal line. Balancers enlarged into circular disks that are cupped and bent downward and show venation but are bare of bristles except for weak ones at rear margin. Stalk of balancer wide and flat. First abdominal segment shows thoracic modification (modification of anterior portion is metathoracic-like, posterior portion is partially mesothoracic-like). Rudiments of a first pair of abdominal legs and, in certain combinations, of partially wing-like first abdominal halteres may occur. Interactions with other bithorax pseudoalleles described by Lewis (1951, 1955, 1963). RK3.
cytology: Locus probably 89E3-4 (E.B. Lewis).
color figure: P. A. Otto (original)
b & w figure: Bridges and Morgan, 1923, Carnegie Inst. Wash. Publ. No. 327: 225 (original drawn by Edith M. Wallace)