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Einiosaurus



    Here is the Einiosaurus stuff.  Once again, criticize anything, 
suggest anything (particularly regarding taxonomy) HURT ME BEAT ME USE ME!!  
One little question I asked before: in the Horner, Varrichio, and Goodwin 
paper in Nature ("Marine transgressions and the evolutuion of Cretaceous 
dinosaurs"), Einiosaurus and Achelousaurus are described as "transitional taxa
B & C".  Transitional taxa A is a form "identical to Styracosaurus except that
it posseses only one pair of parietal spikes" like Einiosaurus and 
Achelousaurus.  I've never heared of this thing.  Has it been described? 
    Also, any additional publication references would be appreciated.

LN Jeff 

"Remember the time you laughed so hard at your own joke that you snorted 
and inhaled at the same time?  Then you choked on your own spit and fell 
over and bonked your head on the coffee table."
"I'm ignoring you."
"Who says your life is boring?"
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GENUS: _Einiosaurus_ (Sampson,1995b)
Synonyms: _Styracosaurus_*1

_Einiosaurus_ _procurvicornis_ (Sampson, 1995b)
Etymology: Blackfoot Indian eini ("bison")*2 + Greek sauros ("lizard") 
           Latin pro ("forward") + curvus ("curve") + Greek cornu ("horn") 
Synonyms: "_Styracosaurs_ makaeli_"*1 
Holotype: MOR 456-8-9-6-1
Referred specimens: MOR 373 (includes multiple specimens), MOR 456 (includes 
multiple specimens)*3 
Formation & location: Two Medicine Formation,
                      Montana, United States
Age: Late Campanian
Taxonomy:
CERATOPSIA Marsh, 1890
CERATOPSIDAE Marsh, 1888
CENTROSAURINAE Lambe, 1915
     Sampson (1995b) considers _E_._procurvicornis_ to be a taxa with 
close ties with _Achelousaurus_ and _Pachyrhinosaurus_, while Horner et all 
(1992) postulate it was a direct intermediate between a _Styracosaurus_-like 
form and  _Achelousaurus_. 

Estimated adult skull length: ~1.5 m

     _Einiosaurus_ _procurvicornis_ is characterized by its unusual nasal 
horn, which curves forward in a manner similar to a bottle opener.  Some 
individuals have smaller and more erect horns, a difference which  may be 
due to sexual dimorphism. The supraorbital horn cores vary considerably in 
morphology from low, rounded masses to pitted surfaces.  _E_. _procurvicornis_
also posseses a single pair of parietal spikes, a character it shares with 
_Achelousaurus_.  _Einiosaurus_ was an average sized centrosaur for its time.  

*1: Dinosaurs: A Global Veiw has a Douglas Henderson restoration of two 
dead floating Einiosaurus labelled "Styracosaurus makaeli".  Where did 
this name come from?  was it just cooked up for the book, or is it 
elsewhere in the published litterature?   
*2: I have recently been informed that all the North American critters we 
call "buffalo" are technically bison, and that there have never been true 
buffalo in North America.  If this is B.S., let me know.
*3: My understanding is that multiple individuals were grouped under a 
single specimen numebnr.  Why was this done?
*4 (PUBLICATIONS): Can someone find out the volume of this one?
 
PUBLICATIONS
Horner, J.R., Varricchio, D.J., Goodwin, M.B. 1992. Marine 
   transgressions and the evolution of Cretaceous dinosaurs. Nature 
   358:59-61.
Morell, V. 1987. Announcing the birth of a heresy. Discover (March):26-50.
Rogers, R.R. 1990. Taphonomy of three dinosaur bone beds in the Upper 
   Cretaceous Two Medicine Formation of northwestern Montana: evidence 
   for drought related mortality. Palios 5:394-413. 
Sampson, S.D. 1995a. Horns, herds, and heiarchies.  Natural History 
   104(6):36-40
Sampson, S.D. 1995b. Two new horned dinosaurs from the Upper Cretaceous 
   Two Medicine Formation of Montana; with a phylogenetic analysis of the 
   Centrosaurinae (Ornithischia: Ceratopsidae).  Journal of Vertebrate 
   Paleontology 15(4):743-760