This was the home of Capt. John Cross, who appears on Loma as early as the 1887-88 Los Angeles City Directories. Here's a little about him:
Aug 6, 1911,
Los Angeles Times @ Newspapers.com
A photo of his home appeared in the Oct 21, 1892,
Los Angeles Times. It's not much of a photo . . .
Newspapers.com
. . . but it was enough to ID that house as the one in the following two photos:
1989-0761 @ CA State Library
That might be Capt. Cross over on the right side of the house. I think the dog closest to him has something around its neck:
1989-0763 @ CA State Library
Here are the house and its neighbors on the 1906 Sanborn (north is on the right):
Library of Congress
The Mary Andrews Clark Home was built across the street from 339 Loma in 1912; both are marked on the aerial below:
1928 Jan 1 Flight c-300 Frame k-166 @
UCSB
Then in 1931-32 Third Street was constructed through the area, with many properties being purchased for the right-of-way:
April 24, 1932,
Los Angeles Times @ Newspapers.com
Both 331 and 339 Loma were in the path of the new Third Street. 331 was demolished in April 1931, but at some point 339 was
rotated 90 degrees, moved just a bit to the south, and renumbered 343 Loma:
1945 Sep 24 Flight c-9770 Frame 16 @
UCSB
Sometime between Sep 1945 and May 1950, 343 (ex-339) Loma was demolished or moved. The May 1950 Sanborn Map has
343 Loma covered up, but you can still see where it was (again, north is on the right):
Library of Congress
Captain Cross' old home on the SWC of Third and Loma was replaced by a Cancer Clinic. That same building is still there
today:
May 28, 1950,
Los Angeles Times @ Newspapers.com