Lymphatic vessels begin in peripheral tissues and ultimately drain into

The right and left subclavian vein.

Explanation:

It is known that lymphatic vessels flushes the tissues, collecting waste products, bacteria, and damaged cells, and then drains as lymph into "left and right subclavian vein".

sheep is a herbivore animal whereas grasshopper belongs to the class chordates but both of them feed on greens.  

if grasshopper and sheep feeding on a pasture land, i do not think both of them will have any impact on each other. however, the number of the species can make difference. since sheep feed on greens, there is a possibility there left no pasture land for the grasshoppers or they may get extinct.