Collection of tax at source: timber rate lowered, half-yearly returns mandated and strict payment and liability rules enforced. Collection of income-tax at source under section 206C was amended to reduce the timber rate (where not obtained by forest lease) to five percent, require half-yearly returns for collectors, and impose a Union surcharge on collections. A proviso excludes deemed profit determination for certain alcoholic liquor transactions where goods were not acquired by auction and sale price is fixed by law, removing the obligation to collect under section 206C. Collections must be deposited within seven days; failure to remit exposes the collector to prosecution and makes the seller liable where the collector omits to collect.