Something that I've noticed whilst doing this thread is how misinformation spreads and almost becomes set in stone until someone actually questions it. In two separate books I’ve read the false assumption that the Brimstone and Cleopatra were one in the same species, and there’s several statements about the Heath Fritillary being found in the south of Ireland. I’ve actually had conversations with Millerd (mostly in-between Brown Hairstreaks at Bookham) about how different authors merely copy their predecessor rather than doing their own research and this is most clearly shown when looking at the supposed foodplant of the Silver-Spotted Skipper:
Humphreys, 1859: The caterpillar feeds on Papilionaceous plants, such as Birds-foot Trefoil, and others of the family. On the continent it is known to feed on Coronilla varia.
Stainton 1867: no note.
Morris, 1870: The caterpillar feeds on the Various-coloured Coronilla on the continent
Newman, 1871: The caterpillar feeds on the Common Birds-foot, Birds-foot Trefoil and other leguminous plants.
Lucas, 1893: The larvae is said to feed on Birds-foot and Birds-foot Trefoil, and possibly other plants of the order Leguminosae.
W. E. Kirby, 1895: It feeds on Coronilla and other Leguminosae.
Gorden 1900: It feeds on Lotus and other small leguminous plants from April to June
South, 1906: from Frohawk in 1901 “he noted a female hovering close over plants. Presently it settled on a tuft of Hair Grass Aira caespitosa, and after walking over and among it a little time, she curved her abdomen down, and deposited a single egg on one of the fine hair like blades…”
W. F. Kirby, 1907: It lives on Coronilla varia and other papilionaceous plants in early summer.
Rowland-Brown, 1912: A single brooded species, the eggs are laid upon various grasses (and, according to some authorities, on Birds-foot Trefoil and allied plants).
W. F. Kirby, 1913: The caterpillar….. feeds on Trefoil etc.
Furneaux, 1919: The caterpillar feeds on certain Leguminous plants, among which are the Birds-foot and the Birds-foot Trefoil.
Stewart, 1926: It feeds on Vetches and Trefoils.
W. E. Kirby, 1928: It feeds on Meadow Grass, Couch Grass, Fescue, and other grasses.
Sanders, 1939: Grasses, chiefly Sheep’s Fescue, also Tufted Hair Grass.
Stokoe (based on South) 1944: Sheep’s Fescue, Hair Grass, Birds-foot Trefoil, Common Birds-foot Vetch and possibly other Leguminous plants.
Stokoe 1969: from Frohawk “they are laid singly on the fine blades of Hair Grass”.
Only one man of the era seemed to know the truth, and why? Because he actually went out and reared them from start to finish. (I’m sure others knew as well but the prevailing view did seem to take root very strongly with many of the big names of the time!)
It wasn’t just the text that was copied either, look at this first image from my oldest book, Humphreys Genera & species of British Butterflies, 1859.
And compare it to South’s book from 1906 (South used Frohawk’s findings so was correct in the text but still illustrated the caterpillar on a legume).
And from there we have Stokoe’s book on caterpillars of British butterflies from 1944 (he stated it fed on grasses AND legumes here)
And Stokoe’s entry in his Observers book (my ’77 reprint of the ’69 edition where he reverted to quoting Frohawk)
Anyway, talking about the great man himself, here’s my copy of his 1934 condensed version of Frohawk's original magnificent work. I think this is a later reprint, not a first edition, hence why I could afford it! There’s no messing around with the LHP choice for the Silver Spotted Skipper here (and this was known from at least as early as 1901 given South quoting him in his 1906 book).
This book has 32 colour plates and 150 b&w drawings including many interesting abs
Not really much else to say except the detail he goes into is amazing, he was way ahead of his time, but I couldn’t not leave without mention of the Large Blue. Most of the species get four or five pages to themselves, the Large Blue gets a whole ten! Here’s a little bit of Lepidopteran history

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