Coe and Runkel— California Limbless Lizard. 391 
similar to those in the cavity of the pineal eye. Whether these 
processes are really cilia or not is rather difficult to determine. In 
the preparations studied, they were rather irregular in length and 
somewhat tapering in form instead of being uniform in diameter like 
true cilia. The cavity of the epiphysis contains, also like the pineal 
eye, a coagulum in the form of a loose network. ‘The epiphysis is 
entirely closed in late embryos and in the adult, and its cavity exhib- 
its no structural connection with either that of the brain or of the 
pineal eye. This also corresponds to what has been determined for 
Anguis by Francotte (’96). . 
In median sagittal sections of the thalamencephalon the posterior 
and superior commissures are seen lying close together a short dis- 
tance in front of the optic lobes, the superior being the smaller and 
situated dorsally. The epiphysis is a hollow oval body lying entirely 
separate from the brain proper except for the connective tissue 
sheath around it. The cavity of the third ventricle is extended 
dorsally as a fingerlike evagination, the post velar arch, reaching as 
far as the dorsal limit of the epiphysis and lying in contact fre- 
quently with the anterior wall of the latter. The velum transversum 
hangs down from the dorsal wall of the third ventricle in front of 
the “Zirbelpolster” and bears at its ventral edge a commissure cor- 
responding probably with the rudiment. of the fornix described by 
Rabl-Riickhard (’81)._ Immediately in front of this the evagination 
of the paraphysis passes dorsally and posteriorly and extends dorsal 
to both the post velar arch and epiphysis. The cerebral hemispheres 
lie in front of the paraphysis. Projecting from the roof of the 
ventricle immediately in front of the opening of the paraphysis is a 
portion of the ependyma which supports the choroid plexus of the 
lateral ventricles. 
Pineal Eye. 
As in a large number of other lizards, the presence of a pineal eye 
is indicated on the exterior by a scale which is differentiated to form 
a kind of “cornea.” In Anniella it is the interparietal plate which 
bears an unpigmented area in its central portion, beneath which the 
deeply pigmented pineal eye is visible (pl. xxu, fig. 10). Usually, 
in the adult at least, the eye is situated in the anterior portion of the 
plate in the middle line, but in some of the embryos at hand it lies 
more posteriorly. The unpigmented area is circular in outline, 
although its outline is not absolutely definite because of the gradual 
disappearance of pigment from the browspot. The eye has a diame- 
ter of about 0.2™" and the unpigmented area a diameter approxi- 
mately twice as great. 
