Jansy Mello: On his visit to London’s Baker St. 221B, as a tease, a friend posed in front of a collection of framed butterflies and observed to me: “Sherlock Holmes also loved butterflies.” Here is what I found in the internet related to this information:

“Butterfly collecting was one of the most popular naturalist crazes of Victorian times. Many private gentlemen had museum-quality collections assembled through collection and purchase”[  ] "Will you come upstairs, Dr. Watson, and inspect my collection of lepidoptera?" 

Conan Doyle: The Lost World Chapter 7 "The scientific attainments of Professor Summerlee are too well known for me to trouble to recapitulate them[  ] Since landing from the boat he has obtained some consolation from the beauty and variety of the insect and bird life around him, for he is absolutely whole-hearted in his devotion to science.  He spends his days flitting through the woods with his shot-gun and his butterfly-net, and his evenings in mounting the many specimens he has acquired. http://sirconandoyle.com/oldsite/novels/lostworld/07.php

The Hound of the Baskervilles Chapter 12: " ‘Oh, excuse me an instant! It is surely Cyclopides.’ A small fly or moth had fluttered across our path, and in an instant Stapleton was rushing with extraordinary energy and speed in pursuit of it. As he often did, Conan Doyle apparently pulled a species name out of the air to designate Stapleton's butterfly. This species name is outdated, and was used to designate a group of species of insect, rather than one specific type. In any case, no insect named Cyclopides is found in Dartmoor at any time of the year. Many other butterfly species do make the moor their home[  ]

 “All my unspoken instincts, my vague suspicions, suddenly took shape and centred upon the naturalist. In that impassive colourless man, with his straw hat and his butterfly-net, I seemed to see something terrible -- a creature of infinite patience and craft, with a smiling face and a murderous heart.[  ]"But are you sure of this, Holmes? How do you know that the woman is his wife [and not his sister]?" http://sherlockholmes.stanford.edu/print_issue6.html

I also passed through Conan Doyle’s affair with the spiritualist world and a few British fairies:

WIKI: “The Cottingley Fairies appear in a series of five photographs taken by Elsie Wright (1901-1988) and Frances Griffiths (1908-1986), two young cousins who lived in Cottingley, near Bradford in England[  ] The pictures came to the attention of writer Sir Arthur Conan Doyle, who used them to illustrate an article on fairies he had been commissioned to write for the Christmas 1920 edition of The Strand Magazine. Doyle, as a spiritualist, was enthusiastic about the photographs, and interpreted them as clear and visible evidence of psychic phenomena. Public reaction was mixed; some accepted the images as genuine, but others believed they had been faked[  ] In the early 1980s Elsie and Frances admitted that the photographs were faked, using cardboard cutouts of fairies copied from a popular children's book of the time, but Frances maintained that the fifth and final photograph was genuine. The photographs and two of the cameras used are on display in the National Media Museum in Bradford.”

While working thru the usual search-engines I found the famous lines attributed to Shuangtzu or Zhuangzi, already presented at the VN-L at different times: “Once I dreamt I was a butterfly, a butterfly flitting and fluttering around, happy with myself and doing as I pleased. I didn't know I was myself. Suddenly I woke up and there I was, solid and unmistakably myself. But I didn't know if I was myself who had dreamt I was a butterfly, or a butterfly dreaming he was me.”  Zhuangzi.*

Now the lines appeared to me in a different context, still related to “Pale Fire,” concerning the debates about one or two authorship theories, in a more refreshing, non-psychopathological mood: is the novel a product of only one dreamer?

This initial query demands the affirmative answer: “Yes, Nabokov” and opens the way to another question: “who is Zhuangtzi, who is the butterfly?” Another question could be: “where and how does JS’s or CK’s Hazel come in and how to relate her appearances to the spiritual dimension?”

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*-JM to JF: “Jerrie Friedman wrote beautifully about his reading of "Pale Fire" and shared his vision with us where  a "red admiral" became "the" thing. But Friedman also implied a level of apprehension like Taoist Chuang Tzu´s story about having dreamt that he was a butterfly and upon awakening finding himself not as certain as he´d been about who he was: a Chuang Tzu person ? A butterfly dreaming Chuang Tzu? (i.e: are dreams more real than our conscious vigil-state sense of "I am"?)
17 Mar 2005  https://listserv.ucsb.edu/lsv-cgi-bin/wa?A2=ind0503&L=nabokv-l&F=&S=&P=72942

JF to JM: “But contrary to what you said, I don't think the red admiral is "the" thing.  I was just supporting my argument with Boyd's contention that the butterfly is Hazel's ghost, which convinced me.  So it's not "my" butterfly (as you said in your other post of yesterday), and I really didn't have a Chuang Tsu-like undecidability in mind.” 
18 Mar 2005 https://listserv.ucsb.edu/lsv-cgi-bin/wa?A2=ind0503&L=nabokv-l&F=&S=&P=79833