Discussion:

On the verso of this work, there is an inscription:  Ambach.  Apparently, this is a reference to Gabriel von Max’s country estate in Ambach on Lake Starnberg (Starnberger See) in southern Germany (Bavaria), presumably the setting of this drawing and where it was created.  

The dark monkey at the far left appears to be Gabriel von Max's favorite monkey, a female capuchin monkey named Paly that he owned since around 1901 until its death in 1915; the other monkey appears to be a green monkey (Chlorocebus sabaeus). Capuchin monkeys are New World monkeys of the subfamily Cebinae; they are considered the most intelligent of the monkeys native to the South and Central America.  

The picture was in the artist’s estate upon his death, from where it devolved through his descendants (from his son Colombo to his granddaughter Gabriele) until The Daulton Collection acquired it from a Munich dealer representing one of the principals; that dealer has consistently dated this gouache at 1915, the year that Gabriel von Max died (on November 24). The capuchin monkey Paly, shown in a bassinet at the far left of the picture, died in mid-February 1915. Therefore, this artwork can be conservatively dated no later than February 1915. Paly’s presence in the bassinet may suggest that the monkey was ill and that the picture depicts a household scene not long before the monkey’s death. The Lenbachhaus catalogue thus dates the picture at “um [about] 1914”; similarly, the Czech catalogue dates it at 1914.  Therefore, a date of circa 1914, or 1914-15, seems pretty solid.

For a 1914 albumen print photograph of Gabriel von Max, his wife Ernestine, and these two monkeys in the collection of the Städtische Galerie im Lenbachhaus, Munich, see Karin Althaus and Helmut Friedel, eds., Gabriel von Max, Malerstar, Darwinist, Spiritist (München: Hirmer Verlag, 2010), p. 314, ill. 321.