Asplenium platyneuron plant. Similar buds have also been reported from the single-sorus spleenwort, "Asplenium monanthes". The species most similar to "Asplenium platyneuron" is the black-stemmed spleenwort, "A. resiliens". However, this stipe of this species is darker, and the pinnae are opposite, rather than alternate, along the rachis. Neither black-stemmed spleenwort nor the other pinnate American spleenworts have dimorphic fertile and sterile fronds. It might be confused with a young Christmas fern, "Polystichum acrostichoides", but that species is generally much larger and has a green, scaly stipe and rachis. It is very similar to Boydston's spleenwort, "Asplenium × boydstoniae", a backcross with Tutwiler's
What Is Life in the UK as perhaps the strongest of all of Harrison's singles. Writing in 1981, "NME" critic Bob Woffinden grouped "What Is LIfe" with "My Sweet Lord", "Isn't It a Pity" and "Awaiting on You All" as "all excellent songs". Reviewing the 2001 reissue of "All Things Must Pass", for "Rolling Stone", James Hunter wrote of how the album's music "exults in breezy rhythms", among which "the colorful revolutions of 'What Is Life' ... [move] like a Ferris wheel". The following year, in Rolling Stone Press's "Harrison" tribute book, David Fricke included "What Is Life" among his selection of "essential