This is a new edition of a dictionary that has been developing for nearly 20 years. Its third edition now has over 6000 entries and 654 pages, and is very good value at the price, especially for students.

Trying to keep such a work up to date must be an unenviable task for any one author and, inevitably, some subject areas are better served than others. For instance, the palaeontology is uneven in its coverage, with a slightly strange smattering of entries on certain individual fossil genera and species, such as Aegyptopithecus zeuxis, Asteriacites and Monotrematum sudamericanum. Whilst Aegyptopithecus zeuxis is certainly important as a basal anthropoid, it is now known as Propliopithecus zeuxis. It is not quite clear how and why these and the other listed species have been selected, and why important genera such as Eusthenopteron have been left out.

Also, cross-referencing between entries could be improved. For instance, the genus Homo is not listed individually although it does come under the Hominidae – fair enough. But under the Hominidae there is no mention of any of the species in the genus Homo, not even the Neanderthals (Homo neanderthalensis) and yet there is an entry for ‘archaic sapiens’ with no cross-reference to or from the Hominidae. There is also an entry for Ardipithecus ramidus, as the ‘earliest-known member of the human lineage’ (What about Orrorin and Sahelanthropus?), but it is not mentioned as one of the genera of the Hominidae.

These are specialist criticisms for what is a much more general dictionary and I mention them as much out of sympathy as anything else for any single author trying to cover such a huge subject area. If some fossil genera and species are to be covered, where does one stop? You cannot win; someone is bound to complain. I imagine that palaeontology is particularly difficult, simply because of the rate at which significant new finds are made and named, compared with new minerals or rocks.

This edition also has an increased number of line drawings, an additional 50 or so, according to the publisher's flyer. Earth Science lends itself to useful explanatory diagrams but many of those presented here are over-simplistic, for instance the illustration of a ‘subduction zone’, and there is no illustration of a mid-ocean spreading ridge or plate tectonics in general, which would help the description. Meanwhile, there are a number of very simple drawings of various brachiopods and other fossils which are not particularly illuminating.

This edition is also advertised as ‘web linked’, which amounts to a single page that lists organizations such as the American Geological Institute but does not give web addresses. Instead the reader has to go to http://www.oup.com/uk/reference/resources/earthsciences and then follow the links to the relevant site. For palaeontology the only site given is www.palaeos.com.

However, used in conjunction with a book such as the recently published Earth Science Data by Paul and Gideon Henderson (2009, Cambridge University Press), this dictionary is still to be recommended to Earth Science undergraduates as a useful starting point.