My article 'On Knowledge Contamination' (Sutton 2016) reveals who really did read Matthew's book and the original ideas on natural selection in it before 1858 and their relationships to Darwin and Wallace, their friends and influencers and influencer's influencers - as opposed to the myths started by Darwin that no naturalists/no one whatsoever did so before Matthew brought his work to Darwin's attention in 1860.
In his notebook of books to read Darwin wrote in 1842 - in the same year he completed his first private essay on natural selection that he should read Vol 8 of the Gardener's Magazine. That volume contained Loudon's (1832) review of Matthew's book.
Darwin wrote: "March 12th Gardener’s Magaz. Vol 7th. & 8th. vol."
However, whilst this main volume ordering ran throughout the series, it must be added that each decade had a sub-order of volumes that began at vol 1 all over again. So we can see that volume VIII of 1832 is displayed as such:
We cannot know, but Darwin might have meant (though if he did he did not write it) that he wanted to read volumes 7 and 8 of the new 1840's decade - written as "new series". We can see how vol VIII of the new decade - "new series" - is displayed in 1842.
The fact Darwin made his notebook entry in 1842 and that Vol. 8 of the new decade was in that same year is highly suggestive that Darwin meant vol VIII of 1842.
Darwin's lies after 1860 - when Matthew's first letter to the Gardener's Chronicle informed him of Loudon's review - and his complete lack of curiosity regarding the conveyance of that fact, and of the fact - conveyed in Matthew's second letter to the Gardener's Chronicle - that another naturalist had read his original ideas and feared pillory punishment were he to teach them, should be weighed in light of the fact that before his Origin of Species (Darwin 1859) was completed, Darwin - apparently - did own Vol. 8 of 1832. And owned it from 1838 - the year he opened his first private notebook on evolution). I've not established the veracity of this (if its true, it's not easily verifiable online) but Andrew Norman ( 2013) p. 173 writes with great exactness and certainty that Darwin owned these. Note however, that he tells us very clearly is only what is inside the front cover of Volume 7, of 1831 when (as his writing clearly shows he knows) Loudon's review is in Volume 8 of 1832:
Further Dysology attached to this story
At the time of writing a website of The University of South Carolina has confused the Gardener's Chronicle with the Gardener's Magazine
They write:
London: Longman, Rees, . . . 1831. Original glazed cloth. Purchased from the C. Warren Irvin, Jr. and Josie B. Irvin Endowment.