
The context of these photographs (ie the location at which they were taken, the time period, and the fact that Dr. Melendez did not know what breed this was when it might have been easy for him to identify these dogs as Great Danes, leads me to believe that these are photographs of the now extinct Spanish "Alano". Research I have done has suggested to me for years that today's Great Dane is very similar in appearance to the Alano of the past.

Because this is Dr. Melendez' father, this photograph can be positively dated to 1904. At some point during the 20th century, the Alano breed became completely extinct. Those dogs in Spain currently being called "Alano" are modern "reconstructions". If you have seen pictures of the reconstructed dogs you will know that they much more closely resemble today's Presa Canario that they do the Great Dane and I think that this is a mistake on the part of those doing the reconstruction.
The now extinct Alano breed of Spain was undoubtedly very similar to those dogs in England which were referred to as "Alaunt" by Edward, second Duke of York in his book entitled "Master of Game". There were three varieties of Alaunt, according to Edward, these being A) Alaunte Gentile, B) Alaunte Veutreres, and C) Alaunte of the Butcheries (another "butcher's dog). He says that especially the Alaunte Veutreres and the Alaunte of the Butcheries made especially good bull baiters and boar hunters. I would imagine that the type of Alano depicted above would have been similar in type to one of these two types of Alaunte.
The history of both the Alano and of the Alaunt (if they were at all different in the past) probably goes back to a group of people known as the "Alans". To make a long story short, the Alans were a group of people who were established in Southern Russia around 230 AD, but who were attacked and defeated by the Huns about 374 AD. After this defeat, many of the Alans migrated westward and joined the western Germans. Some of their tribe eventually settled in Gaul in France's Loire Valley while others settled as far west as Spain and Portugal at about 411 AD. In any event, they brought their dogs with them and these are the dogs which carried their name during the time of Edward and until much more recently in Spain. For further information on this subject, I refer you to my chapter entitled "The General Background of Dogfighting" in my first book "The World of Fighting Dogs".