So I have recently come upon this link which I have found to be very informative and was wondering how accurate it is.
It seems more-or-less as though an indented block is meant to signify hierarchy, so I'm going to proceed on that assumption. Maybe it's a wrong assumption, but I think my meaning will come across regardless.
2/10, would not recommend
The page says of the Ainur:
The Ainur who came into the west of Arda were called the Valar
Which is not true. The Valar were the fourteen1 most powerful of the Ainur who entered Arda, but the Maiar are also Ainur
It's not totally clear what Ents are, precisely. It's certainly possible that they're Maiar, but it's by no means confirmed
Also if you're going to include Ents, then the omission of the Great Eagles is a bit baffling; both races are introduced in the same paragraph of The Silmarillion:
When the Children awake, then the thought of Yavanna will awake also, and it will summon spirits from afar, and they will go among the kelvar and the olvar, and some will dwell therein, and be held in reverence, and their just anger shall be feared. For a time: while the Firstborn are in their power, and while the Secondborn are young." But dost them not now remember, Kementári, that thy thought sang not always alone? Did not thy thought and mine meet also, so that we took wing together like great birds that soar above the clouds? That also shall come to be by the heed of Ilúvatar, and before the Children awake there shall go forth with wings like the wind the Eagles of the Lords of the West.'
The Silmarillion III Quenta Silmarillion Chapter 2: "Of Aulë and Yavanna"
Tom Bombadil is a complete mystery; grouping him with the Ents is a bit incongruous, because we have no idea what he actually is.
The page seems to imply that "Quendi" means "first born of Illuvatar", which is untrue; "Quendi" means something like "those who speak" according to The Silmarillion:
Themselves they named the Quendi, signifying those that speak with voices; for as yet they had met no other living things that spoke or sang.
The Silmarillion III Quenta Silmarillion Chapter 3: "Of the Coming of the Elves and the Captivity of Melkor"
The page says of the Eldar:
When summoned to Valinor in the 1st Age (before the keeping of time)
Which is wrong on two levels:
- What we call the First Age is more accurately called the First Age of the Sun, because it began when the Sun and Moon first went up into the sky. The First Age began some time after the rebel Noldor returned to Middle-earth from Aman, long after the initial summons
The keeping of time began with the blooming of Telperion and Laurelin, the Two Trees:
[U]pon the mound there came forth two slender shoots; and silence was over all the world in that hour, nor was there any other sound save the chanting of Yavanna. Under her song the saplings grew and became fair and tail, and came to flower; and thus there awoke in the world the Two Trees of Valinor.
Telperion was the elder of the trees and came first to full stature and to bloom; and that first hour in which he shone, the white glimmer of a silver dawn, the Valar reckoned not into the tale of hours, but named it the Opening Hour, and counted from it the ages of their reign in Valinor. Therefore at the sixth hour of the First Day, and of all the joyful days thereafter, until the Darkening of Valinor, Telperion ceased his time of flower; and at the twelfth hour Laurelin her blossoming. And each day of the Valar in Aman contained twelve hours, and ended with the second mingling of the lights, in which Laurelin was waning but Telperion was waxing. [...] Thus began the Days of the Bliss of Valinor; and thus began also the Count of Time.
The Silmarillion III Quenta Silmarillion Chapter 1: "Of the Beginning of Days"
The Elves were first discovered 1085 Valian Years after this, and weren't invited to Aman until YT 1101.
The misstatement about the First Age is repeated under the Noldor; it's not clear when the Noldor are formally exiled, but the Kinslaying occurs in YT 1495, and the Prophecy of the North is spoken in YT 1496; the First Age wouldn't begin until YT 1500, with the rising of the Moon and the Sun
The linked page says of the Teleri:
Never went to Valinor. Settled in Middle-earth
This is an oversimplification. Although the Nandor and Sindar never crossed the Sea, the Falmari (eventually) did reach Valinor, founding the haven of Alqualondë.
Typo: "Falarmi" should read "Falmari"
Hobbits really should be classified as a sub-group of Men; they're a derivative species
As well, as Mithoron notes in a comment on the question, the order of creation is totally wrong. Then again, I'm not entirely sure the page is trying to convey the order of creation, so I'm not counting that against it.
On the "positives" column, the hierarchy of the Elvish subgroups looks fairly good (though it's not entirely fair to say that the Nandor settled in Ossiriand; one subgroup of them did, but another stayed in the Vale of Anduin and became known as the Silvan). I'll also give them credit for being vague about the Orcs, because that origin story is a hot mess of conflicting narratives.
On balance, I'd recommend this very site over St. Bonaventure's page for your Tolkien needs.
1 Or fifteen, depending on if you count Melkor