Ermine

                                    

                                          

The stoat (Mustela erminea), also known as the Eurasian ermine or ermine, is a species of  native to  and the northern regions of Eurasia and the northern regions of North America.
Ermine fur was used in the 15th century by someone who sometimes used it as the  cape. It has long been used on the ceremonial robes of members of the United Kingdom.
In North America it is called a short-tailed weasel. 
A male stoat is called a dog, hob, or jack, while a female is called a jill. 
The group for stoats is either gang or pack.
The stoat is similar to the least weasel in general proportions.
Males are roughly 25% larger than females and 1.5-2.0 times their weight.
 On average, males measure 187–325 mm (7.4–12.8 in) in body length, while females measure 170–270 mm (6.7–10.6 in). The tail measures 75–120 mm (3.0–4.7 in) in males and 65–106 mm (2.6–4.2 in) in females.
The winter fur is very dense and silky, but quite closely lying and short, while the summer fur is rougher, shorter and sparse. In summer, the fur is sandy-brown on the back and head and a white belly. 
The stoat molts twice a year. In spring, the molt is slow, starting from the forehead, across the back, toward the belly. In autumn, the molt is quicker, progressing in the reverse direction. The molt. 
Notice it in the winter it has a black tail-tip during the winter period. 
The differences in the winter and summer coats are less apparent in southern forms of the species. In the species' southern range, the coat remains brown, but is denser and sometimes paler than in summer.