The following article explains the Field Medical Service School training that all Corpsmen have to go through before being attached to a Marine unit.  It was copied from a Sept. 1969 "Leatherneck Magazine" article.
January 5, 2007
This a photo of Tim Shalk and Keith Miller taken in 1967 when we went through Hospital Corps School in San Diego and then through Field Medical Service School at Camp Pendleton together. It was  good memories back then.  Tim recently contacted me and we've been going back and forth through e-mail.  Tim's the first and only corpsman I've come across from our old company.  It's great to hear from him and thanks for the photo Tim.
Tim and his wife, Eileen, taken in 2005 onboard an Alaskan Cruise.
Field Medical Service School, Camp Pendleton - Company "D"                                              October 1967 
Last night at FMSS before we shipped out. (L-R) Stanton,?,?,?,? Tim, Keith, Kuck, Rocha, ?.

Tim and friend (?) while he was attached to the  MCB10, 31st Naval Construction Reg ( Seabees ).
On bivuac at Field Medical School training at  Pendleton.
Still celebrating with Ramos on left standing, Keith,  Tim and Tanaka.  The others I can't remember.
(L-R) Whaley, Tim, Wilkins,  Moss and Dunning - I think.