A large scale 13CO(J=1-0) survey was made for CMa OB1/R1 region in 220° ≤ l 230° and -10° ≤ b ≤ 10° with a 8' spacing by using the 4 m radio telescope of Nagoya University. 34 isolated clouds were identified in this survey. Among them, two clouds were firstly identified by us. The observed LSR velocity indicate that almost of the all clouds are located in the Local arm, except two extreme velocity. The mass spectrum of the clouds in the Local arm is best fitted by a power-law index of 1.6.

• BONG GYU KIM(Korea Astronomy Observatory, Department of Astrophysics, Nagoya University)
• AKINO KAWAMURA(Department of Astrophysics, Nagoya University)
• YASUO FUKUI(Department of Astrophysics, Nagoya University)