Joint and several liability of partners confirmed for firm tax obligations; successor and predecessor assessed according to succession date. Under Section 188, when one firm succeeds another (excluding cases under section 187), the predecessor is assessed up to the date of succession and the successor is assessed after that date. Under Section 188A, every person who was a partner during the relevant previous year and the legal representative of any deceased partner are jointly and severally liable with the firm for tax, penalty or other sums payable by the firm, and the Act's assessment and recovery provisions apply to such liability.