394 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
the external surface of the ascending process (a. p.) of the quadrate. 
This bone was known to Cuvier (T7, p. 87) as the ‘temporal. Duges 
(’35) called it the jugal and in this has been followed by the cousins 
Sarasin (’90). Stannius (’56) called it the squama temporalis, Wieders- 
heim (’79) the squamosum, and Cope (’89) the squamosal. Huxley 
(’71) regarded it as the squamosal plus the quadratojugal of the Anura, 
while Gaupp (’94) thought that probably it corresponded to his para- 
quadrate and in this conclusion he has been followed by Peter (’98). 
Fig. A. — Reconstruction of the temporal region of the skull in Ichthyophis 
(larval stage), a.p., ascending process of quadrate; OC., otic capsule; 
Pa., parietal; Pf., postfrontal; Pt., pterygoid; Qu., quadrate. 
Gegenbaur (’98, p. 377, fig. 232) homologized it with the quadrato- 
jugal- 
As already pointed out, its position in the larva does not warrant its 
consideration as the squamosal. Its identification as jugal or quad- 
rato-jugal is negatived by its early history and relationships, while the 
fact that in the adult it articulates with the maxillary is apparently, 
as maintained by Peter (’98, p. 594), a secondary condition. As 
pointed out above, Gaupp’s paraquadrate is merely a synonym of 
squamosal. 
What, then, is the homology of this bone? The postfrontal sug¬ 
gests itself, especially when it is found that this bone in the embryo 
