CHONDROCRANIUM OF EUMECES 123 
scales are clearly visible in the epidermis, and the longitudinal 
stripes of the juvenile color pattern are already conspicuous. 
Stage 5, which is in nearly the same stage of development as 
the 3l-mm. embryo of Lacerta described by Gaupp, furnishes 
the foundation for this paper, but earlier and later stages are 
used freely for comparison. 
The material was preserved in picro-acetic and stained with 
Mallory’s triple connective-tissue stain (acid fuchsin +aniline 
blue +orange G)—a stain which leaves nothing to be desired as 
regards clearness of differentiation of bone and cartilage from 
one another and from surrounding tissues. 
The following wax plate models have been available for study 
and comparison: 
a. Stage 1. Membranous labyrinth, modeled by Mr. J. I. Taggart. 
b. Stage 2. Entire skull and first two vertebrae, cartilage only, 
modeled by Miss Margaret Cole. 
c. Stage 5. Entire skull and first two vertebrae, cartilage and bone, 
modeled by the author. 
d. Stage 5. Cavity of otic capsule, modeled by Mr. J. I. Taggart. 
e. Stage 5. Membranous labyrinth, modeled by Mr. J. I. Taggart. 
f. Stage 5. Brain and nerve roots, modeled by Mr. Clarence L. 
Turner. Figure and brief description published by Mr. Turner (’14). 
g. Stage 6. Posterior portion of skull, cartilage only, with nerve 
origins, modeled by the author. 
3. BASAL PLATE AND ASSOCIATED PARTS 
1. Basal plate and occipital condyle 
The basal plate (figs. 1 and 2), belonging alike to the occipital 
and otic regions, lends itself to separate and continuous descrip- 
tion. As in Lacerta, the basal plate consists of a dorsally con- 
cave floor between the otic capsules and extending from the 
foramen magnum at the posterior to the fenestra hypophyseos 
at the anterior. The anterior margin is strikingly thickened to 
form the crista sellaris (fig. 1, cr.sel.), and from the anterolateral 
corners arise the trabeculae cranii (fig. 2, trab.), the rudimentary 
pilae prooticae (fig. 1, pz.pr-ot.), and the basipterygoid pro- 
cesses (fig. 2, pr.b-pt.), which will be described in detail later. 
