Polypodium vulgare L. var. auritum Willd

Abstract

American fern students seem to differ in regard to their conception of Polypodium vulgare L. var. auritum Willd.; the characteristic ear-like appendages borne on fronds of that fern, being described as occupying various positions. My attention has been recently called to this matter, by an article in the American Fern Journal (Vol. 1, pages 7-9) Polypodium vulgare in Maine, by Henry W. Merrill, where the statement appears that the true var. auritum is not eared on the upper side of the segments. On page 8, Mr. Merrill says ,Still another form has been found that, unlike auritum, which has ears on the lower side of the pinnme, has ears on the upper edge of the pinnae only. Mr. W. N. -Clute says that this form is new, and the finder is hunting for a name, but so far he has been unsuccessful. Mr. Merrill, unfortunately, does not attempt to substantiate his assumption that the true var. auritum is not eared on the upper side of the segments and I am unable to conceive what ground he has for this belief. Polypodium vulgare L. var. auritum Willd. is a form found occasionally in New England, easily distinguished from other varieties by the presence of ears or auricles on the lowest segments next to the midrib. These ears or auricles may be borne on the upper border, on the lower border, or on both upper and lower borders of the lowest segments. Considering the fact that American botanists have only recently evinced active interest in fern variation, it is not surprising that' meagre descriptions of these most interesting forms are found in American textbooks, or perhaps no mention of them whatever, and that they are not well understood. For instance, our most pretentious (25)