multas: etc., the exaggeration of the expression marks the intensity of the poet's grief over the distance that separated him from his brother's deathbed and tomb.
 inferias: defined by Servius on Verg. A. 10.519 “inferiae sunt sacra mortuorum, quod inferis solvuntur” . Perhaps Catullus is now offering the cena novemdialis, omitted perforce up to this time, since none of the family were present at the burial. In this case the offerings would be especially dishes of eggs, lentils, and salt, and the phrase in v. 9 multum manantia fletu would be quite in point, as it would not be if libations only were offered.
 interea: with an imperative, indicating the relinquishment of the previous line of thought, at least for a season; cf. Catul. 14.21; Catul. 36.18; Verg. Cir. 44ff. “haec tamen interea … accipe dona meo multum vigilata labore” .
 ave atque vale: the offerings are concluded with the final farewell that should have been spoken at the burial. The fullest form of this conclamatio was salve, vale, ave, but other forms are mentioned; cf. Verg. A. 11.97 “salve aeternum mihi, maxime Palla, aeternumque vale” ; Servius on Verg. A. 2.644; and the selection of forms occurring in inscriptions in the index to Wilmann's Exempla Inscr. Lat. 2. p.692.