Industrial sick benefit insurance is hereby defined as that form of insurance for which premiums are payable weekly and which provides for the payment of a weekly indemnity on account of sickness or accident in addition to a benefit in case of death. Such death benefit shall not exceed one hundred and fifty dollars ($150.00).  There shall be a provision for the payment of weekly premium, eighty percent (80%) of which shall be allocated for the purchase of sick and accident coverages and twenty percent (20%) thereof for the purchase of death benefits. (1945, c. 385.)