From the Robin Catalogue:
One letter (fragment) to CSP, n.d.; one postal card to CSP, Rome November 26, 1900; one telegram to CSP, March 20, 1903; several letter drafts and fragments of drafts from, most of which are dated or have been dated, with the dates ranging from [April 1897] to [December 25, 1909].

Published, in part, as EP 2:492-502; and NEM 3:788-878 (“L224: [April 1897], [c. 18 April 1903], 18 April 1903 [two letters from William James Collection], [August 1905], 26 February 1909, 25 December 1909 [William James Collection]).

Collected Papers, Cross-reference index:
“Correspondence, 1897-1909, in the William James Collection,
Houghton Library. [CP] 6.478n*, 8.117n10, and 8.249-315 are from it.
Cf. [CP] 7.44n17 and 8.39n1.”