In case you're ever called upon to draw some animals, you may want to brush up on this flickr set of scans from Robert Lambry's les Animaux tels qu'ils sont [Animals as they are].
Lambry's instructions were originally made for l'Echo du Noel in the 1920's and 30's, a weekly Catholic children's paper published by Maison de la Bonne Presse until 1936. [Bonne Presse was owned by Bayard, which is in turn owned by the Augustines. These images come from an unsold set of 51 editions of l'Echo du Noel from 1931 on eBay.fr.]
A Spanish translation [Los Animals tul cual] came out in 1941, but so far the earliest French edition of Les Animaux tel qu'ils sont I've found mentioned is from 1949. [The authors are listed as R. y L. Lambry, so someone--a brother or wife, perhaps--is getting shortchanged on her credit for the book. Desole', madame.] The 1959 edition has a whopping 200 pages and promises to teach this "reputedly difficult subject [sujet réputé difficile]" in just 95 simple lessons. Et voila!
In the mean time, Lambry also published a more comprehensive drawing manual in 1938, le Langage des Lignes, which looks like a prime target for awesome vintage clip art pilfering.