"Caprice" then seems to have been introduced as the marque for the French issue of JWH cards. A "baby" card very similar to the example here but with a date of 1900 has the extended legend "Editeur J.W.H à B. No 76 Sch. phot: Caprice. Reproduction interdite" running up the side of the card, and on the address side "Caprice. No. 2503." The fourth example card, posted in 1901, has got rid of J.W.H. à B. and put JWH in a shield below the Caprice legend on the address side.
There is a Wikipedia article on the artist of the first two cards, Jack Abeillé (1873-1939). He is one of several French artist-illustrators who Anglicised his first name.
The Reutlinger photo 1507 is part of a series that was very popular around the turn of the century. Examples appear in both JWH (German) and French (Caprice) versions, both with the JWH shield logo. The original photos on a number of album pages are at gallica.bnf.fr/ark:/12148/btv1b8596921x/f24.item. They were used by publishers including KViB, NPG, RPH, and SIP in several countries, often with elaborate surrounding designs. An example in this collection is in the Glückstadt & Münden entry.