Auxin Collected 



- 0.3 



22 



,».V,i.i.w.u.u.^;.7.;.;.;.:.;.;,;,v; 



H 



DISTANCE FROM TIP OF AVENA COLEOPTILE.M 



Fig. 4. Relation between auxin transport and mean cell 

 length in 30 to 33 mm. long Avena coleoptiles. Transport 

 data are from Went and White (25), cell-length data from 

 Avery and Biirkholder (1). 



AGE OF SEEDLINGS, DAYS 



Fig. 5. The gradual development of basipctal auxin iraii-sport in the tip of young 

 bean hypocotyls. The solid triangles represent native auxin; open circles represent 

 native auxins plus added lAA. Solid lines represent auxin in base to apex collec- 

 tions; dashed lines represent auxins in apex to base collections. Data from Jacobs (8). 



