Ferry, Lancefield and Metz: jMutations in Drosophila 383 



Characters Not Yet "Placed" 



The following- mutant characters are 

 known to he inherited, hut their link- 

 age relations have not yet heen worked 

 out. \\'ith the possihle exception of 

 hroken. they are all autosomal char- 

 acters. 



Branched (br). 



Description. — The usual manifesta- 

 tion of the character hranchcd is a 

 short hranch running" distally from the 

 posterior cross-vein at or near its junc- 

 tion with the fifth vein, or a hranch 

 from the fifth vein toward the margin. 

 All the veins are slightly thicker than 

 usual. The character is unsatisfactory 

 to work' with, for it seldom appears in 

 the males and it does not always ap- 

 pear in the females. 



Origin. — (R323). One female was 

 found in triple stock. 



Lacking (/). 



Description. — Lacking is distin- 

 guished by the absence of one or both 

 of the posterior scutellar bristles, but 

 the character is not constant and some- 

 times fails to be manifest. 



Origin. — ( RGOtS ) . Several males 

 and females were found in the second 

 generation of a mating for small 

 bristles. 



Cone (en). 

 Figure 21 



Description. — The first tarsus is 

 shortened and broadened at its base 

 giving it a cone shape. The other tarsi 

 are also shortened. This condition is 

 most extreme on the hind legs, but it is 

 also seen to a lesser degree on the other 

 two pairs. The wings may be l)ent 

 down over the abdomen, although this 

 is not a constant characteristic. Since 

 cone males are sterile, ])ure stock can- 

 not be maintained. 



Origin. — (R'^Oll). One male was 

 found in the third generation from a 

 mating of blunt approximated by rough 

 clipped. 



Jaunty (j). 



Description. — In jaunty fiies the 

 wings are of a very thick and opaque 

 texture and turn up at the tip. Gen- 

 erally the wings do not entirely unfold. 



Origin. — (R2128). Several yellow 

 scute jaunty females were obtained 

 from the first generation of a mating 

 of rough rimmed stump by yellow- 

 scute. 



Comparison. — Jaimty bears a general 

 resemblance to jaimty and the jaunty- 

 like characters in D. nielanogaster^' but 

 it cannot be identified with any par- 

 ticular one at present. 



Literature Cited 



^ Bridges, C. B. The Mutant Crossveinless in Drosophila iiiclanogastcr. Proc. Nat. 

 Acad. Science, 6:6m. 1920. 



^ Bridges, C. B., and T. H. Morgan. The Second Chromosome Group of Mutant Char- 

 acters. Carnegie hist., Wash., Pub. 278:12.3-304. 1919. 



^Clausen, R. E. Liheritance in Drosopliila Iixdei. I White and VermiHon Eye-Colors. 

 Amcr. Nat., 57:52. 1923. 



* Lancefield, D. E. Linkage Relations of the Sex-Linked Characters in Drosophila 

 obscura. Genetics, 7:335-384. 1922. 



° Hagedoorn, a. L. and A. C. Species Crosses in Rats. Zcits. f. iud. Abs. it. ]\-rcb. 

 29:97. 1922. 



" Lancefield. R. C. and C. W. Metz. The Sex-Linked Group of Mutant Characters in 

 Drosophila zvillistoni. A >ner. Nat. 61 -.211-241. 1922. 



''Metz, C. W. An Apterous Drosopliila and Its Genetic Behavior. Amcr Nat. 48:675- 

 692. 1914. 



^ Metz, Moses and Mason. Genetic Studies On Drosopliila I'lrilis, etc. Carnegie hist. 

 Wash. Pub. 328. 1923. 



^Morgan, T. H. and C. B. Bridges. Sex-Linked Liheritance in Drosopliila. Carnegie 

 Inst. Wash. Pub. 237. 1916. 



^^ Sturtevant, a. H. Genetic Studies on Drosophila siniitlans. Ill Autosomal Genes. 

 General Discussion. Genetics 6:179-207. 1921. 



^^Weinstein, a. Homologous Genes and Linear Linkage in Drosopliila z'irilis. Proc. 

 Nat. Acad. Science, 6:625-639. 1920. 



