बृहत्साम तथा साम्नां गायत्री छन्दसामहम्। मासानां मार्गशीर्षोऽहमृतूनां कुसुमाकरः ॥

bṛihat-sāma tathā sāmnāṁ gāyatrī chhandasām aham māsānāṁ mārga-śhīrṣho ’ham ṛitūnāṁ kusumākaraḥ

Of hymns also Brihatsâman; Gâyatrî of metres am I; of months I am Mârgasîrsha; of seasons the flowery.

In plain words: Krishna says among sacred songs he is the Brihat Saman, a great hymn. Among poem rhythms he is the Gayatri, a holy chant. Among months he is Margashirsha, in late autumn, and among seasons he is spring, the season of flowers.