Sirmio, the modern Sermione, is a long and narrow peninsula running out into the southern end of the Lago di Garda (Lacus Benacus). The ruins referred to by Tennyson (l.c.) are of the age of Constantine, but are called by the natives the Villa of Catullus in accordance with the mediaeval identification
 ocelle: the gem cf. in this sense Aesch. Eum. 1025 “ὄμμα πάσης χθόνος” ; Pind. Ol 2.9 “Σικελίας τ᾽ ἔσαν ὀφθαλμός” ; Plaut. Trin. 245 “o ocelle mi” (as a pet name), Cic. Att. 16.6.2 “ocellos Italiae villulas meas.”
 libenter … laetus: a not infrequent collocation. cf. Pl. Trin. 821 “laetus lubens laudes ago” (the speaker here also has just returned from a foreign shore), and at the end of dedicatory inscriptions, e.g. C I L 6.533 “POSVIT·L·L” (i.e. laetus lubens）
 Thyniam: the Thyni, a people from Thrace, are said to have settled that portion of Bithynia which lay close to the Thracian Bosphorus and was sometimes said to be divided from Bithynia proper by the river Psilis; but the two names, long before the time of Catullus, had ceased to express any actual distinction.
 larem: the guardian deity of the household, worshipped with the penates at the hearth. The plural occurs but once in Plautus ( Pl. Rud. 1206 “ut rem divinam faciam laribus familiaribus” ), and the word not at all in Terence; but from this time down the plural is common as a designation for the home, especially in connection with penates with which divinities the lares came to be practically identified.
 Lydiae: if the reading is correct, the lacus Benacus was so called from the well-known Etruscan settlements in the Po region. The Etruscans were traditionally of Lydian origin, and are often called Lydians by the poets; cf. Verg. A. 2.781 “Lydius arva inter opima virum leni fluit agmine Thybris” ; Hor. S. 1.6.1 “Lydorum quidquid Etruscos incoluit fines.” With the transfer of epithet from lacus to undae cf. Verg. l.c. quidquid and Catul. 17.19n.