OF THE GREAT AUK, OR GARFOWL. 325 



The nasals, confluent behind with the frontals, prefrontals, and lacrymals, soon divide 

 into their premaxillary (PI. LI. fig. 2, is) and maxillary ( is) branches ; the former, at 

 first divided by a fissure from the nasal part of the premaxillary (22), coalesce therewith 

 anteriorly ; the longer styliform maxillary processes coalesce by their lower end with the 

 maxillary. 



The broad part of the palatal plate of the maxillary (ib. fig. 3, 21), whence its palatine, 

 malar, nasal, and premaxillary processes diverge, is perforated by the oblique foramen (/) 

 conveying the lacrymal and superorbital secretions to the angle of the mouth. The pre- 

 maxillary processes are divided by the back part of the long prepalatine fissure (/), 

 about 2 lines in breadth. The malar process is depressed, about an inch in length, and 

 underlaps the fore half of the malar. The nasal process rises to the inner side of, and 

 is partly confluent with the maxillary process of the nasal bone ; which process 

 (ib. fig. 1, 15') is subcyhndrical, and extends downward and forward from the interspace 

 between the lacrymal bone and the premaxillary part of the nasal, dividing the large 

 external nostril ( is) from the antorbital ( 21') vacuity. 



The premaxillary chiefly forms the compressed, subarcuate, pointed upper mandible, 

 which is grooved on the narrow palatal surface (ib. fig. 3, 22" ) for an extent of 1 inch 6 lines 

 from the apex, where the prepalatal vacuity commences. The fore end of the groove is 

 divided by a short delicate median ridge. The nasal process of the premaxillary (22) 

 assumes behind the rostral part of the bone a trihedral shape, gradually becoming flat 

 and then concave below ; it is grooved above, the groove deepening to a fissure, and 

 dividing the back part of the process where it joins the frontal. The nasals (15) are also 

 partly divided by linear fissures from this part of the premaxillary, with which they are 

 confluent at both ends. 



The pterygoids (fig. 3, 24) are slender, slightly bent, trihedral bones, articulating ante- 

 riorly to short pterygoid processes at the inner and back part of the palatines, and pos- 

 teriorly with an articular tubercle on the inner side of the base of the inner division of 

 the lower articular end of the tympanic (28). The limits of the styliform malar 

 (ib. fig. 3, 26) and squamosal (27) are indicated by grooves ; the latter articulates with 

 the outstanding lower and outer angle of the tympanic. 



The tympanic articulates by two convex condyles with the mastoid and paroccipital ; 

 its body slightly contracts below these, and sends from its fore part a long compressed 

 triangular process, with the apex obliquely truncate ; its lower end is much expanded, 

 and supports two articular surfaces : the outer one (fig. 3, 28) is oblong and oblique, 

 convex anteriorly, and concave posteriorly, where it is extended upon a short posterior 

 process, forming the squamosal cup ; the inner and smaller facet is convex, and above 

 this is the pterygoid tubercle. 



The lower tympanic condyles are adapted to two corresponding cavities on the 

 articular part of the mandibular ramus, which developes behind them a vertical trian- 

 gular surface, the outer and inner margins of which are produced into cristse. There 



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