RE: ABOUT THE REVERSED HALLUX AND...

[Emma Rainforth <EmmaR@mesalands.edu>]

In response to Tim:

> Is the hallucal impression as deeply imprinted as the other three digits?
> This will tell you if the hallux was lowered as well as reversed.

No. All the 'hallux' impressions are identical to each other, nicely
triangular, and look like they belong to a toe that was flat on the ground.
(Which, if they are actually undertracks of digits 2-4, is not implausible).

(BTW Lull's 1953 monograph is *still* available for sale from the
Connecticut State Survey; call the Connecticut Dept. of Environmental
Protection bookstore...)


> > As Swan assures us, the Anchisauripus ichnogenus is unquestionably
> > theropodan.
> 
> Is he still correct?

Don't see any reason he isn't!
Incidentally, aside from a couple of new species erected by Lull for new
material, the varisou Anchisauripus species were removed from Grallator and
Eubrontes (aka "small tridactyl" and "big tridactyl" - both of which are
considered theropodan.


And in response to Ray :-)

"Lull's fidelity to accuracy": the collection he was studying - essentially
revising the work of Ed and Chuck Hitchcock - was in an poorly lit basement
in Lull's time (well, part of his time. The rest of the time, it was in
storage, including much of the early part of the twentieth century). IMHO
(and other ichnologists concur) - one should trust Lull 1953 about as far as
you can throw it. On second thoughts, DEFINITELY not that far.....

Steropoides: a fine example of crappy tracks if ever there was one. 

DO NOT TRUST A SINGLE DRAWING BY LULL!!! EVER!!!!!
The drawings are mostly composites (stated in his 1904 thesis, out of which
the 1915 & '53 monographs grew), with a little restoration here and there,
and incidentally did I mention they look NOTHING like th specimens? At ALL?

(Oh, another little itty-bitty problem is Lull screwed up just about every
type specimen ID. HE based it mostly on CH Hitchcoc k 1865 (the Catalog in
the appendix to Ed H's Supplement) - which in turn is transcribed from Ed's
handwritten notebook, with a few edits here and there. Ed had a tendency to
say of nice specimens, they were 'typical' of the taxon. Lull interpreted
this to mean "the type specmein' whereas the intent was 'a nice track'.
(sigh)
And as for the taxonomy, Ha. In 1904 he states he followed Hay 1902 (the
first Bibliog & cat. Of fossil verts of N. America) - even though Hay made
some mistakes (because he was working from Hitchcock 1865 and the collection
was in storage at the time so he couldn't actually look at specimens).
Anyhow, that's unfortunate, but heck, Hay was signing off on Lull's
dissertation.....

Ok, back to Steropoides: about all you can say is it's a dinosaur with 3
anteriorly-directed digits and a highly variable hallux impression
(variability largely due to difference in preservation between specimens).

Arachnichnus: is a cute l'il thing. Quadrupedal. 3 anterioirly-directed
digits on the pes. Uh. Can't really say a whole lot else about it. 

>    You commented, about Lull declaring a theropod origin for
>Anchisauripus, "...[golly, I'd LOVE to know HOW Lull "knew" this]), though
>we now know Anchisaurus to be a prosauropod - although, Anchisauripus is
>almost certainly a Theropod (and therefore NOT the track of Anchisaurus)."
>Is there any possibility that he got the idea that it is of theropod origin
>of Anchisauripus for the same reason that we now reason it had that origin?
>-- or was that too early in 'paleontological time'?

Howeve, his rationale for it being a theropod is more or less sound,
although he doesn't test the hypothesis - I think it was purely accidental. 

He "decided" it was the track of a theropod, and Anchisaurus (which he
thought was a theropod) fitted in terms of age and size. Incidentally, he
thought (in 1915) Eubrontes was a herbivore track - he put it in a different
ichnofamily. 
Unfortunately he *diagnosed* Anchisauripus as being the track of
Anchisaurus, and a theropod track - with the hallux "when present" being the
main distinguishing feature between it and Grallator and Eubrontes
(remember, he removed some of the species from G and E into his new genus).
Ironic given the hallux doesn't exist.....
. 

>    It would have been very nice if Lull had been able to provide high
>resolution photos of the tracks, but the printing would have been much more
>expensive, even though it might have shown the error of his interpretation.

Heck, even today, ichno-photos are quite often poor and you can't tell
anything anyway. (The only track photo in the 1915/1953 monograph is
reproduced from Marsh';s 1896 Dinosaur tome. Incidentally, that photo is of
Steropoides. Judge for yourself - beats me how Lull got his nice drawing
from those specimens!!!)


emma