Two verses from two works. Rāmāyaṇa CE R_6,090.027 (GRETIL sa_rAmAyaNa.txt); Mahābhārata CE 05,141.007a/007c (GRETIL mbh1-18u.zip). Griffith omits the Rāmāyaṇa omen passage entirely — his Book VI jumps from Canto LXXV to XCIII — so the translation quoted is Dutt's.
A deity-derived alias for Rohiṇī (Prajāpati is Rohiṇī's presiding deity), attested INDEPENDENTLY in both epics and, in the Rāmāyaṇa, with the identification made inside the verse: 'Mercury, mounting the Prājāpatya asterism, ROHIṆĪ, the moon's beloved, stood there, bringing ill to creatures.' The Mahābhārata occurrence (Udyoga 5.141.7, Karṇa's omen speech) uses Prājāpatya alone; Ganguli, translating the vulgate, silently substitutes 'the constellation called Rohini', which either reflects a vulgate reading rohiṇīṃ or is his gloss — either way it confirms the equivalence. The database already carries the closely related 'Prājeśa' from the later siddhāntas; Prājāpatya is a distinct form and is not yet recorded. Cross-reference: prajesha, rohini.