Now Ctrl+click on the frog layer to make selection and with clone tool fill the selected areas on tongue layer.Then hit Ctrl+Shift+I (Select Inverse) and Delete. Deselect (Ctrl+D).You can delete the frog layer too if you want, you wont need it anymore. Resize and rotate the tongue if necessary (I had to make it slightly bigger) and blend the lower edge with face layer using layer mask, eraser or clone tool.