24 ILLINOIS BIOLOGICAL MONOGRAPHS [24 
palatine cartilage as Gaupp interprets it.”” Gaupp (1893, footnote p. 430) 
says: “Hierzu méchte ich bemerken, dass ich die beiden Namen ‘Antor- 
bital-fortsatz’ und ‘Cartilago palatina’ durchaus fiir dasselbe Gebilde 
gebraucht habe (17, p. 115: ‘die Cartilago palatina’ oder wie die englischen 
Autoren Huxley und Parker den Knorpel nennen, den ‘Processus antor- 
bitalis’). Als ‘Processus palatinus’ wird der Knorpel aber z.B. von 
Friedreich und Gegenbaur bezeichnet (14, p. 29), auch Hertwig (24) nennt 
ihn auf den Figuren ‘Cartilago palatina’ (C.p.), und Wiedersheim (58, p. 
483) spricht von einen Antorbitalfortsatz oder ‘Gaumenfortsatz’ der 
deutschen Autoren. Da ich beide Bezeichnungen in der Literatur vorfand, 
so erwihnte ich sie auch beide, habe aber nicht etwa einem bekannten 
Gebilde eine neue Deutung geben wollen. Kingsley scheint unter ‘Palatine 
cartilage’ hier etwas Besonderes zu verstehen; was das ist, kann ich aus 
seinen Angaben nicht ersehen.” 
Winslow (1898) discussed the question, and concluded that until it was 
shown that the process in Urodeles arising from the trabecula in front of the 
orbit was actually a part of the pterygoquadrate the name antorbital 
should be retained. A further point is that the term palatine cartilage is 
misleading, implying that it is the rudiment of the palatine bone, which is 
not cartilaginous in origin. 
With the evidence now presented by Cryptobranchus, it would seem as 
if the basal part of the process here, and by implication in all Urodeles, is 
really an anterior prolongation of the pterygoquadrate. But the anterior 
portion of this process is something additional, and although possibly 
pterygoidal in origin, may retain the name antorbital. Then in all other 
groups, where the posterior connection to the quadrate is lost, the entire 
outgrowth, although partly pterygoidal, is best known as the antorbital 
process. Of course this retention of the anterior part of the pterygoid in 
both Cryptobranchus and Ranodon larvae is an ancestral feature lost 
elsewhere among the Urodeles. As stated in the above, the adults of both 
species of Cryptobranchus have lost the connection of the pterygoid with 
the side of the cranial wall, and in both the direction of the posterior 
plainly pterygoidal part of the cartilage would not suggest that in the larva 
there was any such connection with the trabecula or any relation with the 
palatine bone. 
Of the Urodeles thus far described, Cryptobranchus stands alone in the 
origin of the planum verticale, which arises as a medial dorsal growth from 
the planum basale, subsequently uniting to the medial margins of the 
columnae ethmoidales and closing off the cavum cranii from the internasal 
space. Thus at no time does a pons ethmoidalis or a fenestra ethmoidalis 
exist in Cryptobranchus, like that in Amblystoma and Salamandra. On 
the other hand the columna ethmoidalis in Cryptobranchus recalls that 
structure in Salamandra which, arising in both from the medial margin of 
