Provided, Further, That mutual marine insurance companies shall include in their return of gross income gross premiums, collected and received by them less amounts paid for reinsurance, but shall be entitled to include in deductions from gross income amounts repaid to policy holders on account of premiums previously paid by them and interest paid upon such amounts between the ascertainment thereof and the payment thereof and life insurance companies shall not include as income in any year such portion of any actual premium received from any individual policyholder as shall have paid back or credited to such individual policyholder, or treated as an abatement of premium of such individual policyholder, within such year; (sixth) the amount of interest, accrued and paid within the year on its bonded or other indebtedness not exceeding one-half the sum of its interest bearing indebtedness and the paid-up capital stock, outstanding at the close of the year, or if no capital stock, the amount of interest paid within the year on an amount of indebtedness not exceeding the amount of capital employed in the business at the close of the year; and in the case of a bank, banking association, or trust company, stating separately all interest paid by it within the year on deposits; or in case of a corporation, joint-stock company or association, or insurance company, organized under the laws of a foreign country, interest so paid on its bonded or other indebtedness to an amount of such bonded or other indebtedness not exceeding the proportion of its paid-up capital stock outstanding at the close of the year, or if no capital stock, the amount of capital employed in the business at the close of the year, which the gross amount of its income for the year from business transacted and capital invested within the United States bears to the gross amount of its income derived from all sources within and without the United States; (seventh) the amount paid by it within the year for taxes imposed under the authority of the United States and separately the amount so paid by it for taxes imposed by the Government of any foreign country; (eighth) the net income of such corporation, joint-stock company or association, or insurance company, after making the deductions in this subsection authorized.

All such returns shall as received be transmitted forthwith by the collector to the Commissioner of Internal Revenue.

All assessments shall be made and the several corporations, joint-stock companies or associations, and insurance companies shall be notified of the amount for which they are respectively liable on or before the first day of June of each successive year, and said assessment shall be paid on or before the thirtieth day of June:

Provided, That every corporation, joint-stock company or association, and insurance company, computing taxes upon the income of the fiscal year which it may designate in the manner hereinbefore provided, shall pay the taxes due under its assessment within one hundred and twenty days after the date upon which it is required to file its list or return of income for assessment; except in cases of refusal or neglect to make such return, and in cases of false or fraudulent returns, in which cases the Commissioner of Internal Revenue shall, upon the discovery thereof, at any time within three years after said return is due, make a return upon information obtained as provided for in this section or by existing law, and the assessment made by the Commissioner of Internal Revenue thereon shall be paid by such corporation, joint-stock company or association, or insurance company immediately upon notification of the amount of such assessment; and to any sum or sums due and unpaid after the thirtieth day of June in any year, or after one hundred and twenty days from the date on which the return of income is required to be made by the taxpayer, and after ten days' notice and demand thereof by the collector, there shall be added the sum of 5 per centum on the amount of tax unpaid and interest at the rate of 1 per centum per month upon said tax from the time the same becomes due.

(d) When the assessment shall be made, as provided in this section, the returns, together with any corrections thereof which may have been made by the commissioner, shall be filed in the office of the Commissioner of Internal Revenue and shall constitute public records and be open to inspection as such:

Provided, That any and all such returns shall be open to inspection only upon the order of the President, under rules and regulations to be prescribed by the Secretary of the Treasury and approved by the President:

Provided, Further, That the proper officers of any State imposing a general income tax may, upon the request of the governor thereof, have access to said returns or to an abstract thereof, showing the name and income of each such corporation, joint-stock company, association or insurance company, at such times and in such manner as the Secretary of the Treasury may prescribe.

If any of the corporations, joint-stock companies or associations, or insurance companies aforesaid, shall refuse or neglect to make a return at the time or times hereinbefore specified in each year, or shall render a false or fraudulent return, such corporation, joint-stock company or association, or insurance company shall be liable to a penalty of not exceeding $10,000.