based on the COA at 
Coats of Arms from Ireland 
and Around the World

Origin: English; First found in Devonshire and in Cornwall, where the family held a family seat since ancient times.

The arms is as follows: "Per fess, the chief sable two trefoils argent, and base argent with sable trefoil"

"Black and Silver with three three-leafed clovers and a border" or "Black and gold shield with a pale counterchanged and three gold trefoils.

Motto:  "Simplex Munditis"

Plant: 

Trefoil (three leaf clover)

Colors: 

Sable (Black) - Constancy, Grief

Argent (Silver or White) - Sincerity, Peace

Notes: Other graphics can be located at: House of Arms, Free Coats of Arms (this one seems different from the others).

Description from James Wolf Heraldry: "Coat of Arms: A black and gold shield with a pale counterchanged and three gold trefoils."

The Simmons name is a sept of the Scottish Fraser clan, whose badge can be seen on the House of Names link above as well as here from My Histories.com

Here is a (related) heraldic bookplate from the Notre Dame Bookplate Registry.

Image - Copyright © 2004 - 2006, Ken Mraz