Valmiki Ramayana Sundara Kanda Sarga 57 Shloka 42
Original Shlokaकेचिदुच्छ्रितलाङ्गूलाः प्रहृष्टाः कपिकुञ्जराः। आयताञ्चितदीर्घाणि लाङ्गूलानि प्रविव्यधुः।।5.57.42।।
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प्रहृष्टाः very exited with joy, केचित् a few, कपिकुञ्जराः elephants among monkeys, उच्छ्रितलाङ्गूलाः lifted their tails, आयताञ्चितदीर्घाणि beautiful and long ones, लाङ्गूलानि tails, प्रविव्यधुः hit on the ground.
Some elephantlike vanaras who were excited and felt overjoyed lifted their long and beautiful tails and hit them on the ground.