176 PROF. W. K. PAKKEE ON THE STEUCTUEE AND 



hind wall. These preoral, endoskeletal palatines are also confluent with the trabe- 

 culffi, from which they were at first distinct, standing out at right angles from them, 

 and having, if any, a slight curve backwards, naturally looking towards the postoral 

 suspensorium. 



These " visceral " bars are not pedate terminally ; they bound the space in which the 

 inner nostrils (i. n) lie, which have the vomero-palatine wings on their inner side ; these 

 passages are a marvellous width apart, almost thrice that of the outer openings {e.n) ; 

 they are twice as large, and look forwards, but most inwards, following the line of the 

 maxillary arch. 



In extreme contrast with the arrested preoral bars — mere proximal rudiments at best 

 — we have the mandibular pier and arch, the suspensorium, carrying the mandibular 

 rami. 



This is not merely a cartilaginous structure, more or less ossified directly, but there 

 are two large bones added to each pier, and three to each ramus. 



Primarily (see in the Newts, Pis. XL. & XLI.) the suspensorium was a thick 

 segment of cartilage sending upwards three snags for union with the skull proximally, 

 and downwards and outwards a condyle for articulation with the elongated terete 

 Meckelian rod. 



The proximal attachments of this huge suspensorium can be seen from the surface ; 

 below, on the left side, the true head or pedicle is hidden by the pterygoid and 

 parasphenoid ; but on the right side (PI. XXXVII. fig. 1,1kI) it can be seen passing 

 into the basis cranii, with which it is confluent. Above, the ascending process 

 (PI. XXXVI. fig. 1, a.p) is seen as a broad tract of cartilage continuous with the ali- 

 sphenoidal wall. 



It has been ossified to some degree both by the sphenethmoid and pterygoid {sp.e, 

 ■pa) ; but a clear edge of cartilage is seen in front of the foramen ovale (v) running 

 outwards to the third process. 



This third (or otic) process (ot.p) is an angular mass of cartilage confluent with 

 the ear-capsule ; in the angle formed by it with the ascending process a part of the 

 prootic {iir.o) can be seen. The body of the suspensorium is a thick phalangiform 

 mass, ending outwards in the large, oblique, reniform quadrate condyle, which looks 

 downwards and is directed slightly outwards. The upper and the hinder part of this 

 thick bar is unossified, and rises behind the edge of the squamosal into a swelling 

 ridge, a sort of natural hypertrophy of the copious cartilage. 



The lower edge of this mass is notched and produced for the attachment of the 

 epihyal (f.%). The antero-external part is solidly ossified as a quadrate bone(g'); 

 and this is confluent with the pterygoid {ixj)- The upper surface is strongly clamped 

 by the squamosal, which almost buries itself in the substance of the cartilage, as if it 

 had been pressed into it whilst soft and ductile, but it does not graft itself upon it. 

 There is no pterygoid cartilage, now, growing directly out of the fore edge of the 



