Astanga Hrudaya
श्लेष्मस्नाय्वपराच्छन्नः कलाख्यः काष्ठसारवत्। ताः सप्त सप्तचाधारा रक्तस्याद्यः क्रमात् परे॥१०॥
just as the essence gets formed in the trees these are covered with slesman (kapha), snayu (tendenous waxy material) or apara (chorion / placenta); these are seven. Saptaa asaya seven containers: Adhara (asaya) containers/recepticles are seven; the first is of rakta (blood), followed by smrtäh ca
english translation