The name Dryopteris filix-mas forma incisa is attributed by various authors to (Moore) Hayek, Flora von Steiermark. Hayek, however, in this Flora doesn't explicitly mention the rank, but transfers the variety incisa to the genus Dryopteris: "γ <gamma> incisa (Moore) Hay." Am right to think that this does not constititue a status change from var to forma? The listing of subtaxa under filix-mas is introduced by the sentence: "Nach dem Grade der Blatteilung kann man folgende Formen unterscheiden:" (according to the degree of incissions, the following forms may be discerned). The German word "Form" includes forma, no doubt, but is more generic than that, and used in a generic sense elsewhere in the text.
OK, then the correct author citation would be to find the first one that makes the wrong interpretation (sofar I found Weatherby, 1935), so Dryopteris filix-mas f. incisa (Moore) Weath. non Hayek, Am. Fern J. 26[2]: 60 (1935) ?
Yes, if I am following everything correctly. I'd like to have a look at the original papers myself to be certain.
Here's Hayek (1908): bd. 1 - Flora von Steiermark, - Biodiversity Heritage Library end here weatherby: v.24-26(1934-1936) - American fern journal. - Biodiversity Heritage Library
Well, it all seems to hinge on the context and use of the German word Forma. The fact that the forms were listed doesn't prevent valid publication by Hayek: From article 32.1 of the ICBN: But, to your first point, there does seem to be some indication that the Code looks at the author's intent (in this case, specifically re: the word Forma). If, like you suggest, it wasn't meant in the nomenclatural sense, then the Weatherby name would be correct.
I will re-check the usage of the word "Formen" in Hayek's work. Art. 37.3 requires a clear indication of its rank, so if doubt remains, I'll proceed as in 37.3 ex 4. Thanks for your comments!
