Re: New in CJES

[David Marjanovic <david.marjanovic@gmx.at>]

> Aren't haramiyid postcanines supposed to look more or less like this? 
> Er...  Trevor? :-]
>
> Reply to David M:

I repeat the entire text because many people probably didn't get it -- it 
was in HTML, and the version that I got via the list is "plain" text without 
line breaks.

> I only read papers, and don't claim to understand the words!  'Haramiyid' 
> postcanines are something like elongated bowls surrounded by cusps.  A 
> 'dentine-lacking posterior shelf' isn't something I've heard of.

Neither have I. That is clearly odd.

> As it happens, I do have a couple of paragraphs which might contain 
> something or other.  The first is my breif, generalised overview of 
> 'haramiyids'.  I think I'll add the sources as one block below.
>
> "The general picture (by Self, MY ie. me!)
> Kemp, 2005 (p.140-141) provides a concise overview of the postcanines. 
> Harami molars are larger than many of their equivalents from contemporary 
> mammals, but not by much. These are blessed with lots of cusps and are 
> generally double-rooted.

"Generally"...

> The crowns are wide and have a line of three large cusps on one edge, with 
> five smaller ones on the opposing side. As there's a connecting ridge at 
> one end and a basin in between, the general idea is a crater surrounded by 
> a number of hills.
> Originally, it was thought that upper and lower molars were pretty much 
> mirror images of each other, and minor details lead to the establishment 
> of two genera: /Thomasia/ and /Haramiya/. The suggestion was subsequently 
> made that these could also represent uppers and lowers of only one genus, 
> and the discovery of /Haramiyavia/ provided confirmation for that."
>
> (The word order could be confusing.  /T./ contributed the lowers and /H./ 
> the uppers.  I'd better do a quick edit to the directory.)

(And the "best" thing is that *T.* has priority...)

> A slightly more intimate account of a lower molar is provided by 
> /Eleutherodon oxfordensis/ from the Middle Jurassic of southern England. 
> These notes are based on the paper by Butler & Hooker.
>
> "Lower molars
> A pair of the new specimens are incomplete lowers. A Dorset one, BMNH 
> 46851, spent some time rolling around after the death of the owner. This 
> playful behaviour was presumably at the behest of moving water, and it 
> cost most of its enamel. However, the decorative fluting in the basin is 
> preserved and wear was light during life. Seen from the occlusal 
> perspective, the crown is a longish oval with maximum measurements of 2.2 
> and 1.55mm, (length and width respectively, p.189). The highest cusp is on 
> a prominence at the front. This is termed b2. A line of (probably) six 
> cusps runs along a ridge on the buccal side, and there are traces of a 
> broadly similar number on the lingual aspect. Both lines carried on until 
> the back of the tooth. The central basin was surrounded."
>
> Sources and so on
> Dykes TD aka Self MY (amateur webpage): 'Haramiyida' - an internet 
> directory, http://home.arcor.de/ktdykes/harami.htm
> Butler PM & Hooker JJ (2005), New teeth of allotherian mammals from the 
> English Bathonian, including the earliest multituberculates, Acta 
> Palaeontologica Polonica, 50(2), p.185-207.
> Kemp TS (2005), The Origin and Evolution of Mammals, Oxford University 
> Press, pp.331.