208 EDWARD L. RICE 
of ‘intracapsular’ and ‘extracapsular’ courses, here and in Reptilia 
generally, to be harmonized through interpretation of connective 
tissue of recessus as integral part of otic capsule, differences 
then depending upon degree of chondrification of capsular wall 
and relative size of fenestra cochleae. 
13. Crista parotica and processus paroticus perfectly confluent 
in later and more distinct in earlier stages, suggesting independent 
origin and secondary union. No connection of processus par- 
oticus with stalk of columella auris, but conspicuous tendinous 
connection with insertion plate. Only negative evidence as 
regards Versluys’s interpretation of processus paroticus as de- 
tached processus dorsalis of columella auris. 
14. Columella auris conforming essentially to schema of Ver- 
sluys. Processus internus moderately developed, but not con- 
nected with quadrate as in Lacerta; processus dorsalis lacking 
unless represented by processus paroticus; cruciform appearance 
of insertion plate, so striking in Lacerta, destroyed by relatively 
slight development of processus accessorius posterior and absence 
of processus accessorius anterior. 
15. Relations of chorda tympani to columella auris as in 
Lacerta. 
16. Following offered as tentative interpretation of columella. 
Embryonie connective tissue extending from hyoid arch to otic 
capsule endowed, throughout its entire extent, with potentiality 
of cartilage formation. Columella developed in this connective 
tissue, in connection, on the one hand, with hyoid, on other, with 
otic capsule, later separating from both. Thus hyostapes genetic- 
ally related to hyoid and otostapes to otic capsule; entire colu- 
mella none the less a genetic unit. 
17. Complete but gradual fusion of trabeculae in thickened 
ventral margin of interorbital septum. No other evidence for 
paired structure of septum. 
18. Fenestration of interorbital septum, progressive from 
earlier to later stages, interpreted as final result of forces origi- 
nally leading to formation of septum, especially pressure of 
enlarging eyeballs. 
