PURPOSE: To prevent a mailed message from being held in a mail box for a long time by providing the title device with a means for calling a mail box owner based upon the count value of messages stayed in the mail box.

CONSTITUTION: A mail number counter 6 counts up the current number of messages stayed in the mail box. When the number of the counter 6 coincides with the previously set number of messages, the counter 6 instructs the transmission of the messages to a central processing part 4 through a bus 7. The central processing part 4 instructs calling to the memory box owner previously registered in a main memory part 5 through the bus 7 and simultaneously outputs a command to an accumulation control part 3 through the bus 7 to extract the messages concerned successively from an accumulation part 8 and transmit the messages from a network control part 1.