1906.] OF THE TRACHEOPHONE PASSEEES. 135 



Pittidce. — Interorbital septum perforate; postorbital processes 

 small ; temporal fossa extending to the micl-dorsal line ; a 

 more or less well-marked nasal hinge ; maxillo-palatines in 

 the form of short thick spurs, crossing the middle of the 

 olfactory floor and far removed from the median descending- 

 keel of the palatine. 



The Occijntal Region. 



The plane of the occipital foramen slopes obliquely backwards 

 through an angle of about 45°, while the foramen itself is without 

 any marked su,praforaminal ridge, except "in the case of the Pittidse, 

 where it is faii-ly pronounced. Compared with that of the 

 Eurylpemidse the cerebral fossa will be found to project slightly 

 beyond (caudad of) the foramen, instead of sloping forwaixls as- 

 in that group, thereby indicating a larger brain-cavity. The 

 lambdoidal crest is not strongly marked, but the region enclosed 

 thereby is wide, except in the case of Pitta, where this ridge 

 is conspicuous and curves rapidly downwards to pass into the 

 lateral occipital wings, thus decreasing the width of the skull in 

 this region. The cerebellar dome is nowhere very prominent, 

 except in Pseudocolcqites, where it attains a development far 

 exceeding that which obtains in any other member of any of the 

 families now under discussion, inasmuch as it rises upwards far 

 above the level of the lambdoidal ridge and temporal fossse to 

 form a tumid swelling, bounded on either side by the cerebral 

 lobes, which stand out in the form of bullae separated from the 

 cerebellar prominence by deep depressions. The lateral occipital 

 wings bounding the tympanic cavity are turned somewhat for- 

 wards, and tend to approach one another in the middle line more 

 than in the Eurylsemidfe. This is especially noticeable in th& 

 Conopophagidse, Philepittida?, Piprid?e, and Dendrocolaptidfe. 



The Crcmvicd Roof (text-fig. 49 a-d). — The cerebral dome is 

 wide, well rounded, and rises gently above the cerebellar dome. 

 Pitta and Hylactes are exceptions in this respect, the cerebral 

 dome rising much higher than in any other members of the 

 families under discussion. In Pitta this dome is constricted 

 laterally by wide though shallow temporal fossfe, but in Hylactes 

 this region of the skull is full and round, and the temporal fossa 

 confined to a shallow depression immediately above the squamosal 

 pi'ominence. In Synallaxis, Cinclodes, and Pseitdocolaj)tes, among 

 the Synallaxinae, and to a less extent in Xijyhocolajjtes among the 

 Dendrocolaptinfe, the cerebral dome is very markedly depressed, 

 though it is at the same time unusually broad from side to side. 

 The cranium of Pseudocolaptes is further noteworthy in that the 

 roof is marked by a relatively deep median groove, and two lateral 

 grooves marking what answei's, more or less accurately, to the 

 Sylvian fissure o"f the brain (text-fig. 50 g, p. 140). In the Ptero- 

 ptochidfe the form of the cerebral hemispheres is well defined^ 

 but the lateral grooves of the " Sylvian fissure " are very faintly 

 indicated. 



