In the chandas (Vedas) the above rules causing lengthening or the substitution of long ī for the final vowel of the aṅga (stem), do not apply, except in the case of putra,
Thus मित्रयुः, संस्वेदयुः, देवाञ् जिगाति सुम्नुयुः ॥ But पुत्रीयन्तः, सुदानवः (Rig VII. 96. 4).
Vart:- It should be rather stated पुत्र and the rest: as जनीयन्तोऽन्वयः See 3.2.170, for the affix उ ॥,