464 
THE STRUCTURE AND RELATIONSHIPS OF ANCODUS. 
II. THE SKULL. (PI. XXIII, figs. 1-3.) 
It is not practicable to compare in detail the elements of the skull in the 
American and European species, because of the imperfect preservation of the hitter. 
In Europe entire skulls have been found only at Ronzon, and of these Filliol says: 
“ Malheureusement, comme pour tons les autres cranes dont je parlerai dans la suite 
r&rasement subi par les os a 4te tel, qu’ au milieu des lignes multiples correspoii- 
dant aux points de rapprochement des Eclats, il est absolument impossible de 
retrouver une trace bien d^finie de suture.” (No. 1, p. 99.) Comparison between 
the skulls of the species of Ancodus found in the Old and New Worlds, respectively, 
must therefore, for the most part, be confined to the general form and proportions’ 
111 the fossils from Ronzon figured by Koivalevsky and Eilhol the skull is 
remarkably long, low, and narrow. This elongation does not aflect the cranium so 
much as the face, for the orbit is placed rather far back, with its front mar-* in o\'er 
nr, while in Oreodon xi is over m!. The muzzle in front of p? i.s especiaUy con- 
cerned m the elongation, and in A. leptorhynchiis it reaches an astonishing de<- rce 
o length and slenderness, while it is least extreme in A. velauiius. The length of 
the_ muzzle is materially increased by the elongation of the premaxillaries. which 
pioject much m front of the canine. The cranium is not very long, as is indicated 
by the position of the orbits, and is narrow and of small capacitv. The occiput is 
border of m?. A. leptorhyndm^Ax t^-^'W»dnig to the hinder 
opposite to the posterior half of m« wMlfin 7Z 
molar series. The palatal a is entirely back of the 
slightly inflated. The mandible haTo auditory hiilhe are but 
and ,i large prominent angle with' “,™, "'“'’r “•‘"''lll'Oii.rreoiital riiiniis 
nel.ativel, little above the . t 
triang„larsl,.a|,e. The masseterle foe “'’“‘“‘tl lf<*™s is low and of 
The AnreHoan spec“)r™ Urn Fm 'T' J""'- 
have been enumerated. In 2 ITerfZZZZ characters which 
little less so than in the shortest-headed of the R elongated, but 
brachyrhynchiis has a face of only morlc r i species, A. velaunus, but A. 
in this respect to “'."“I,'"-- " ‘‘ 
more rounded and capacious, and the 'f; ^ 
marked. The forehead is much wider and profoundly 
considerably longer. The zygomatic arch is processes of the froiitals . 
curving more downward in its course to tC „“ Tl 
t- I he occiput is low and broad,. 
