The ornamental design for a portabletelephone, as shown and described.
FIG. 1 is a front, top, and right side perspective view showing our new
design for a portable telephone in full lines, with the broken line matter
being for illustrative purposes only and forming no part of the claimed
design;
FIG. 2 is a bottom plan view thereof;
FIG. 3 is a rear elevational view thereof; and,
FIG. 4 is a left side elevational view thereof, with the broken line matter
being for illustrative purposes only and forming no part of the claimed
design.