Beware, too, of the vulgar error of fancying that little duodecimos
with the mark of the fox and the bee's nest, and the motto
"Quaerendo," come from the press of the Elzevirs. The mark is that
of Abraham Wolfgang, which name is not a pseudonym for Elzevir.
There are three sorts of Elzevir pseudonyms. First, they
occasionally reprinted the full title-page, publisher's name and
all, of the book they pirated. Secondly, when they printed books of
a "dangerous" sort, Jansenist pamphlets and so forth, they used
pseudonyms like "Nic. Schouter," on the 'Lettres Provinciales' of
Pascal. Thirdly, there are real pseudonyms employed by the
Elzevirs. John and Daniel, printing at Leyden (1652-1655), used the
false name "Jean Sambix." The Elzevirs of Amsterdam often placed
the name "Jacques le Jeune" on their title-pages. The collector who
remembers these things must also see that his purchases have the
right ornaments at the heads of chapters, the right tail-pieces at
the ends. Two of the most frequently recurring ornaments are the
so-called "Tete de Buffle" and the "Sirene." More or less clumsy
copies of these and the other Elzevirian ornaments are common enough
in books of the period, even among those printed out of the Low
Countries; for example, in books published in Paris.

A brief sketch of the history of the Elzevirs may here be useful.
The founder of the family, a Flemish bookbinder, Louis, left Louvain
and settled in Leyden in 1580. He bought a house opposite the
University, and opened a book-shop. Another shop, on college
ground, was opened in 1587. Louis was a good bookseller, a very
ordinary publisher. It was not till shortly before his death, in
1617, that his grandson Isaac bought a set of types and other
material. Louis left six sons. Two of these, Matthew and
Bonaventure, kept on the business, dating ex officina Elzeviriana.