•196 STRUCTURE AND CLASSIFICATION OF BIRDS 



As Gareod has pointed out, the vomer of the Capitonidae 

 differs from that of the Passeres in being truncated behind 

 the posterior line of the palatines ; in the Passeres the 

 truncation is in front of the line. The skull of Megalama 

 asiatica has been described and figured by Parker.' Outside 

 the Y-shaped vomer there is on each side a small ' septo- 

 maxillary ' splint, and in front' a median unpaired septo- 

 maxillary. The former are, perhaps, the equivalents of the 

 vomers of Picidse {q.v.) ; the vomer in that case may have 

 something to do with the medio-palatine of Picus. The 

 nostrils are impervious and very much reduced by long 

 growths. In Megalama virens and Gymnobucco the lacry- 

 mals and prefrontals entirely fuse with each other and with 

 the skull walls to form a solid and imperforate plate of bone, 

 as in Pterocles, pigeons, toucans, &c. 



There are fourteen cervical vertebra. The atlas is per- 

 forated by the odontoid. The axis and the three following 

 vertebrae have median hypapophyses ; the next vertebra (the 

 ■sixth) has a bifurcate one. All these processes are more 

 conspicuous than in the toucans, where, however, they are 

 3)resent. Vertebrae C11-D6 (last) and LI have strong 

 hypapophyses, that of D2 being bifurcate. In Gymnobucco 

 only three dorsals have hsemapophyses. Five ribs reach the 

 ■sternum, which is four-notched and has a spina externa ; the 

 clavicles do not meet below. The head of the clavicle 

 expands into a wide flat triangular plate. 



Indicator is considered to be the type of a distinct sub- 

 family of the Capitonidae, which also contains the genus 

 Protodiscus. Indicator has been chiefly investigated by 

 Gaueod.^ Nitzsch, however, previously and Fuebringbe 

 •subsequently added to our knowledge of the bird. It has 

 twelve rectrices ; the pterylosis has a marked gap between 

 the anterior and the posterior parts of the spinal tract ; and 

 the latter appears to encircle the oil gland, as in the- 

 ■Capitonidae. 



' ' On the Structure and Development of the Bird's SbuU,' Trans. Linn. 

 .Soc. (2), i. p. 122. 



^ ' Notes on the Anatomy of Indicator major,' P. Z. 8. 1879, p. 930. 



