Embryonic conditions are due to the mixture of the vital seed and blood. On account of insemination the result which first appears is called by the name of 'Kalala.
बिन्दुन्यासादयोऽवस्थाः शुक्रशोणितसम्भवाः। यासामेव निपातेन कललं नाम जायते॥