I am afraid there is no way of knowing for the text just identifies the Desmonds as distant cousins of the Baskervilles.
Near the beginning of chapter 6, we find the following quote from Sherlock Holmes: ". . . I have made some inquiries myself in the last few days, but the results have, I fear, been negative. One thing only appears to be certain, and that is that Mr James Desmond, who is the next heir, is an elderly gentleman of a very amiable disposition, so that this persecution does not arise from him. I really think that we may eliminate him entirely from our calculations. . . ."
The cast of A Voodoo Spell - 1967 includes: Dayton Allen as James Hound
The cast of Bugged by a Bug - 1967 includes: Dayton Allen as James Hound
5 ft 7 in, just like Audrey Hepburn (but they are not related, except by their ancestor James Hepburn of the Mary Stuart era).
The cast of The Hound of Silver Creek - 1928 includes: Frank Clark as John Lawton Edmund Cobb as Jack Brooks Gloria Grey as Molly White Gladden James as Marvin Henley Frank Rice as Slim Terwilliger Dynamite the Dog as Dynamite
Gwendolyn Davis (mother ) And James Davis ( Father )
hound
Mrs. Gill
Dr. (or mister if you please) James Mortimer read it from an old paper written by a Baskerville.
Near the beginning of chapter 6, we find the following quote from Sherlock Holmes: ". . . I have made some inquiries myself in the last few days, but the results have, I fear, been negative. One thing only appears to be certain, and that is that Mr James Desmond, who is the next heir, is an elderly gentleman of a very amiable disposition, so that this persecution does not arise from him. I really think that we may eliminate him entirely from our calculations. . . ."
The cast of Dreamnapping - 1966 includes: Dayton Allen as James Hound
The cast of Frozen Sparklers - 1967 includes: Dayton Allen as James Hound
The cast of Traffic Trouble - 1967 includes: Dayton Allen as James Hound
The cast of Fancy Plants - 1967 includes: Dayton Allen as James Hound
The cast of The Rain Drain - 1966 includes: Dayton Allen as James Hound
The cast of Mr. Winlucky - 1967 includes: Dayton Allen as James Hound
The cast of The Phantom Skyscraper - 1966 includes: Dayton Allen as James Hound