Biva's delicacy and sureness of line features, colors and compositions of bouquets and still lifes comes in part from this particular training—also in the artistic context of Montmartre at the time.

He paid great attention to the subtly nuanced variations of direct and reflected light on flower petals, while using vivid contrasts to highlight the expressive colors of his subject matter.

[8] M. Paul Biva, landscape artist with a particular preference for flowers, was in the genre one of the most skilled and brightest artists of our time; his colorations are always, without ever exceeding the threshold of the natural world, vivid and explosive [éclatantes], and his motifs harmoniously composed [...] many landscapes of always fresh tonality, flowers and fruits, are highly acclaimed and sought after by collectors.

[9] The literature in the press often confuses the two brothers, Paul's work is sometimes likened to that of Henri Biva, the elder who lived 30 years longer, and whose production was therefore much more abundant.

The "Causerie" of Jacques Mauprat, published in Le Progrès Illustré (18 February 1894)[10] mentions 'the flowers of both Biva's' exhibited at the Salon Lyonnais, and in 1993, Élisabeth Hardouin-Fugier and Étienne Grafe, in their book titled Les Peintres de Fleurs en France, de Redouté à Redon[11] repeatedly mention "Biva", without specifying a first name to distinguishing between the two, even though several of their paintings are discussed and reproduced in the ouvrage.

[11] If at first, from 1873, the young Paul Biva was influenced by the zeitgeist for genre scenes and landscapes—electing to paint landscapes that evoke those of Jean-Baptiste Corot—he subsequently explored other paths and other subjects.

His flowers became more expressive, vigorous yet delicate and full of freshness, while Henri Biva's landscapes offered an intimate glimpse of a specific locale, characterized by intricate strokes and a pure palette bathed with warm natural light.