7 
1871.] 2 ‘ 7 [Cope. 
that is forty or fifty feet in length. The remains representing it consist 
of seven cervical and dorsal vertebree, five of them being continuous and 
enclosed in a clay concretion. 
These display the elongate character seen in ZL. laevis, etc., but the ar- 
ticular surfaces are transversely oval, thus resembling the L. ictericus. 
they are less depressed than in L. perlatus and L. dyspelor. The cup 
and ball of the penultimate cervical are alittle more transverse than those 
of the fourth dorsal, and none of them are excavated above by the neural 
canal. The last cervical is strongly keeled on the middle line below, and 
with a short obtuse hypopophysis marking the beginning of the posterior 
third of the length ; the median line of the first dorsal has an obtuse ridge. 
There is no keel on the fourth dorsal, but the lower surface is concave in 
the antero-posterior direction. The diapophyses on the last two cervical 
aud three first dorsal vertebrae have great vertical extent ; the articular 
surface for the rib is not bent at right angles on the first dorsal. Neural 
arches and spines are well preserved in most of the specimens. There is 
no trace of zygantrum. The neural spines are flat, and have consider- 
able antero-posterior extent on cervical as well as dorsal vertebre, and 
are truncate above. The first dorsal bears a long strong rib. 
M. 
Transverse diameter cup penultimate cervical vertebra... .051 
LY OLGiGMaCHAniOUGh Qu:SUINO. fe vait ly os Cin veh ic nine see 041 
Length centrum fourth dorsal, without ball.............. 072 
NiCUULGA CAMELTOE Dall foes Merce. hah ice ud, th isn wietee 0455 
Transverse DOs Fyiepan base wpe Seen area eds Cel hae GoM -0555 
Elevation front margin neural spine penultimate cervical.. .088 
Antero-posterior diameter do. do. 0. .,256.:30D 
There are smooth bands around the balls, and the surfaces of the centra 
are striate to these. 
The depressed cups of the cervicals and anterior dorsals distinguish 
this species from the L. validus, L. proriger and H. mudgei. The same 
elements are much larger and more elongate than in ZL. ictericus. 
It differs especially from these species of Holcodus and from Liodon 
curtirostris in the elongate form of the anterior dorsals ; in the latter, they 
are much shorter and in three of them at least, the inferior limb of the 
diapophysis is turned forwards to meet the rim of the cup, while this 
feature ceases with the last cervical in L. latispinus. The articular sur- 
faces have planes at right angles to the axis of the centrum and are not 
prolonged above as in ZL. glandiferus. The last hypapophysis is very 
short, with the anterior margin transverse and elevated as in the last 
named species. 
In size, this species is intermediate between such gigantic forms as L. 
dyspelor, and the lesser LZ. curtirostris. 
The type specimens were found by Professor B. F. Mudge, one mile 
south-west of Sheridan near the ‘‘Gypsum Buttes.” 
