364 A - Ärnbäck Christie-Linde 



What is said above on the cartilago palatina in monodelphic 

 mammals may be summarized as follows: 



It is most probably homologous with the processus palatinus 

 of Gaupp in Echidna. 



Consequently it belongs to the primordial crane and is origi- 

 nally a processus from the floor of the cartilaginous nasal capsule 

 into the region of the secondary palate. 



It is present in the Reptilia: Lacerta, as the cartilago ecto- 

 choanalis, and in the Monotremata: Echidna, where it reaches its 

 highest development. In a rudimentary State it occurs in monodelphic 

 mammals e. g. Insectivora menotyphla (Tupaja, Macroscelides), Insec- 

 tivora lipotyphla (Soricidae), Rodentia (Lepus cunieulus), Chiroptera 

 (Vespertilionidae, Pteropodidae), Prosimiae {Chirogaleus, Ga- 

 lago). 



It is situated between the premaxillary and maxillary bones 

 and just between the processus palatini of these bones. 



It occurs 



a) quite isolated, the sickle-shaped cartilago ductus naso-pala- 

 tini being absent e. g. Tupaja, Macroscelides, Lepus; 



b) quite isolated, the sickle-shaped cartilago ductus naso-palatini 

 being present, e. g. Chirogaleus; 



c) connected with the sickle-shaped cartilago ductus naso-palatini 

 e. g. Sorex 7 Miniopterus. 



Its function, originally related to the canalis naso-palatinus, 

 has in the course of development been considerably reduced. In 

 higher mammals the cartilago palatina is probably in general of a 

 more or less rudimentary character. Yet it may be of some use as 

 partially supporting the nasal cavity in foetal stages. 



