19th century Pugs, 1. Paintings

The practice to crop the ears of the Pug continued during the 19th century but became more uncommon over time.

Is one of the puppies below brindle, or is it stone gray/silver?

Also below one of the puppies is either brindle or stone gray/silver.

In the litter below we see two stone gray or brindle puppies.

According to one source on the internet the painting below is called “Brindle Pug”, which would then refer to one of the puppies. Since that page is about the color brindle in the Pug the name of the painting could be an invention of the author of that page. (Il mistero del carlino tigrato.) Any information about this or other paintings here are welcome.

19th century Pugs, 2. Photos