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
Translation祖供を運ぶ者(kavyavāhana)、ṛta(宇宙の正序)を増し育てるアグニが、正しく祖霊たちを祭り敬うように。さらにただちに、供物を宣言し告げて、ここへ向けよ—神々へ、また祖霊たちへ。
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)