The C does not have a serif, and the M fills the entire space, touching the top and bottom curves of the C. The opening of the C is quite small, when compared to the other monogram also called "M inside C".
Ipsen was employed as a staff illustrator by the James R. Osgood publishing firm in Boston and also worked for several other local publishers.
In publisher's advertisements and other trade articles, he is often just referred to by his last name, Ipsen.
Laurence Housman was an author and artist who designed many book covers for his own work as well as other authors. When he signed his work, it was typically with a LH monogram.