The adult probation officer of the 222nd Judicial District receives a salary of not less than $15,000 per annum. Also, the probation officer receives allowances, not to exceed the amount allowed by the federal government for traveling the most practical route to and from the place where the duties are discharged, for his necessary travel and hotel expenses. Upon the sworn statement of the officer, approved by the judge, the respective counties of the judicial district pay the expenses incurred for their regular or special term of court out of the general county fund. In lieu of travel allowances the commissioners court of each county, by agreement, may provide transportation under the same terms and conditions as provided for sheriffs.