SB 10.26.16

varṇās trayaḥ kilāsyāsan
 gṛhṇato ’nu-yugaṁ tanūḥ
śuklo raktas tathā pīta
 idānīṁ kṛṣṇatāṁ gataḥ
Synonyms: 
varṇāḥ trayaḥ — three colors; kila — indeed; asya — by your son Kṛṣṇa; āsan — were assumed; gṛhṇataḥ — accepting; anu-yugam tanūḥ — transcendental bodies according to the different yugas; śuklaḥ — sometimes white; raktaḥ — sometimes red; tathā — as well as; pītaḥ — sometimes yellow; idānīm kṛṣṇatām gataḥ — at the present moment He has assumed a blackish color.
Translation: 
[Garga Muni had said:] Your son Kṛṣṇa appears as an incarnation in every millennium. In the past He assumed three different colors — white, red and yellow — and now He has appeared in a blackish color.
Purport: 

This and the next six verses (17 through 22) are taken from the eighth chapter of this canto, in which Garga Muni instructs Nanda Mahārāja about Nanda’s son Kṛṣṇa. The translations found herein for these verses are based on those of His Divine Grace A.C. Bhaktivedanta Swami Prabhupāda. In Chapter Eight, where the verses originally appear, the reader will find extensive purports by Śrīla Prabhupāda.