Electron micrograph maps of divisions 51 through 60 of thin sectioned polytene 2R chromosome of Drosophila melanogaster.

The banding pattern of the distal half, i.e., the divisions 51 through 60, of the salivary gland 2R chromosome in Drosophila melanogaster was studied using thin section electron microscopy. This chromosome region contains 280 single and 157 double bands on the Bridges' revised light microscopic map. Most of the single bands were identified in thin sections; 34 bands were regarded as missing or they could not be reliably shown. In addition, about 20 new, mainly very faint single bands were found. 21 Bridges' double bands were found to be made up of two separate bands each in thin sections.