Mbh 8.45.1d

So Rakshasas and Pishacas protect the Himavat, the best of mountains. The Guhyakas, O great king, protect the mountains of Gandhamadana. Without doubt, Vishnu, otherwise, called Janardana, protects all creatures. (For all that the Vahikas have no especial protectors among the gods). The Magadhas are comprehenders of signs; the Koshalas comprehend from what they see; the Kurus and the Pancalas comprehend from a half-uttered speech; the Salwas cannot comprehend till the whole speech is uttered. The Mountaineers, like the Sivis, are very stupid. The Yavanas, O king, are omniscient; the Suras are particularly so. The Mlecchas are wedded to the creations of their own fancy. Other peoples cannot understand. The Vahikas resent beneficial counsels; as regards the Madrakas there are none amongst those (mentioned above.) Thou, O Shalya, art so. Thou shouldst not reply to me. The Madrakas are regarded on Earth as the dirt of every nation. So the Madra woman is called the dirt of the whole female sex. They that have for their practices the drinking of spirits, the violation of the beds of their preceptors, the destruction of the embryo by procuring miscarriage, and the robbing of other people's wealth, there is no sin that they have not. Fie on the Arattas and the people of the country of the five rivers. Knowing this, be silent. Do not seek to oppose me. Do not let me slay Keshava and Arjuna, having slain thee first."'"