Bermuda-based company, yesterday reported net income of $79.6 million during the second quarter ended April 30, an increase of about 27 percent over the same period last year.

Net income for the first six months was $143.4 million, or $3.63 a share, a gain of 25 percent over the same period ended April 30, 1997. Total revenues increased 16 percent to $335.6 million over the first half 1997. For the second quarter diluted earnings were $2.01 per share compared to $1.65 a share in the same quarter 1997. Net operating income was $68 million, an increase of about three percent over second quarter 1997.

Mid Ocean reported revenues of $169.2 million, an eight percent increase over the $157.4 million in second quarter 1997. Gross written premiums increased about 14 percent to $156.8 million while net premiums earned were $122.8 million, a six percent gain.

Net investment income, excluding net gains or losses, was $28 million a gain of about 11 percent. Net investment gains were $11.6 million compared to $3.4 million in losses registered in second quarter 1997. In April Exel Ltd. agreed to merge with Mid Ocean for about $2.2 billion in stock and cash.