瑜伽論記 6.308

6.308

不如象鼻者，景師等解，垂袈裟角名如象鼻，即此反搭衣疊衣不倒垂下崱屴向上名為龍首，若屈攝在腕名如豆搏。

Regarding 'not like an elephant's trunk', Master Jing and others explain: having a corner of the kaṣāya hang down is called 'like an elephant's trunk'; this very corner, folded and draped back over the robe without hanging down, rising toweringly upward, is called a 'dragon's head'; if it is bent and gathered on the wrist, it is called 'like a bean cluster'.