Rishi: Verify in Vājasaneyin anukramaṇī for VS 19.65.
Devata: Agni (as mediator to Pitṛs and Devas)
Chandas: Triṣṭubh/Jagatī mixed cadence typical of VS Pitṛ passages (confirm by scan).
Samhita Patha (Devanagari)यो अ॒ग्निः क॑व्य॒वाह॑नः पि॒तॄन् यक्ष॑दृता॒वृध॑: । प्रेदु॑ ह॒व्यानि॑ वोचति दे॒वेभ्य॑श्च पि॒तृभ्य॒ आ
Transliterationyó agníḥ kavyavā́hanaḥ pitṝ́n yákṣad ṛtā́vṛdhaḥ | prédu havyā́ni vocati devébhyaś ca pitṛ́bhya ā́
Translationകാവ്യവാഹനായ അഗ്നി, ഋതത്തെ വർധിപ്പിക്കുന്നവൻ, വിധിപൂർവ്വം പിതൃകളെ യജിക്കട്ടെ. ഉടൻതന്നെ അവൻ ഹവ്യങ്ങളെ പ്രസ്താവിക്കട്ടെ—ദേവന്മാർക്കും പിതൃകൾക്കും—ഇവിടേക്കായി.
Padapatha (Word Analysis)यः । अग्निः । कव्य-वाहनः । पितॄन् । यक्षत् । ऋत-वृधः । प्र । इत् । उ । हव्यानि । वोचति । देवेभ्यः । च । पितृभ्यः । आ
Word by Wordकव्यवाहनःcarrier of the kavyas (funeral/ancestral offerings) पितॄन्the Fathers/ancestors यक्षत्may he worship/propitiate ऋतावृधःgrown/strengthened by ṛta (cosmic order) हव्यानिoblations (things to be offered) पितृभ्यःto/for the Fathers (ancestors) 
Entities MentionedP
Pitṛs (Fathers/Ancestors) Viniyoga (Ritual Application)