A.C.BEELER 1969 Mus MUSCULUS Brooks Island, Contra Costa Co., California. Feb 7 About 40 yards NW. 3:15 pm on island. A few minutes taken in same direction. The Mus were all fairly fast but none was breeding - the 10 spec's procured for MVT were picked at random from the total catch. Mus still common on all except possibly the very highest parts of Island. Our spec's were taken at about 10 feet and range up to 50 or 80 feet.