Explanation, Personification, and Poetics

I have a bit of a headache, possibly from reading the Darwin, so I hope this post makes sense...The Botanic Garden (1791, 4th ed.) contains within it classical allusions, Biblical figures, and references to scientific explanations or speculations of the day. These explanations are offered as notes to phrases that are not given an asterisk, number, or Roman numeral, and so it is easy to glide right by them; such avoidance is also easy because the phrases that are cited in the notes do not announce themselves as incongruous; when the Goddess shouts, "Ethereal powers! You chase the shooting stars, / Or yoke the vollied lightnings to your cars," the phrase "shooting stars" does not necessarily leap out from the rest of the passage. Still, that phrase is explained wtih a note on the nature of meteors; thus we learn that a "shooting star" is naturally occurring phenomenon, not an imaginary construct. Of course, the term "shooting star" is not a properly scientific term, but a colloquial term that suggests some sort of analogy or comparison between a "star" that "shoots" through the sky, and the actual meteor that moves through space. Often Darwin's lengthy footnotes run the danger of over-explaining natural phenomena, and rendering them mundane. On the other hand, very often the notes' scientific elaboration of a seemingly fanciful phrase actually makes the phrase more powerful by taking something that appears to be purely imaginary and giving it a real existence--i.e., the mythical creature with "ethereal fire" turns out to be a species of electric eel. Thus in naturalizing certain poetic terms, Darwin's verse suggests the natural "poetic" wonder arising from the natural world. Of course, Darwin's poem does not annotate every figurative expression, and the figures of the "natural Genius," the "Goddess" of nature, and Classical figures such as Jove often go unremarked. In addition, I've noticed that the figure of Love appears here and there in order to hold all of these natural elements together. Very often found objects or tangible phenomena are described in scientific terms--for instance, Darwin includes a note explaining what a comet is--but still personifies the natural processes that act upon these objects (the Goddess exhorts the Nymphs to "Alarm with comet blaze the sapphire plain"). Does the inclusion of personification, metaphor, and other figurative language simply function to represent those parts of nature Darwin is not prepared to explain? Is the reader supposed to automatically understand that those tropes are meant as placeholders for that which is yet to be defined and annotated? Or does the stubborn presence of figurative language in a text that claims to explain Nature's literal existence simply demonstrate the inability of our language or our minds to think without metaphor or symbolic forms? Ok that's all I got (have). I look forward to discussion.