498 ARKIV FÖR ZOOLOGI. BAND 1. 



bill. In a similar way the lower rhamphotheca is composed 

 of two pieces, the median suture between which is quite 

 strongly developed to the extreme tip of the bill. Stränge 

 as it seems, the peculiarly modified bill of Platalea still 

 shows in the most conspicuons manner the same three ele- 

 ments in the upper and the same two in the lower rham- 

 photheca as those which have been described above as occur- 

 ring in the Ibises and in Scopus, the sutures being qnite 

 distinct from the base to the tip of the bill. Faint traces 

 which might be interpreted as indications of a subdivision 

 into infralabial and submandibular onght to be studied anew 

 on fresh material before any decision can be made as to 

 their valne. 



In the bill of the Storks the elements, which may be 

 supposed to be the same as in Scopus and the Ibises, are 

 more fused together, so that for instance the sntnres between 

 the pieces of the upper rhamphotheca are only visible basally 

 and towards the middle of the bill as prolongations of the 

 nasal grooves. This fusion is to be regarded as a result of 

 the much increased massiveness of the rhamphotheca. 



In the bill of Phcenicopterus the upper rhamphotheca 

 consists of the same three pieces as that of the Spoonbills, 

 Ibises etc. and it exhibits a rather striking likeness espe- 

 cially to the first mentioned of these. The lower rham- 

 photheca of the Flamingo has a well developed median 

 suture in the same way as the other birds just mentioned. 

 But in addition to this there is laterally a certain indi- 

 cation to a subdivision into an upper and a lower piece 

 which then might represent an infralabial and a submandi- 

 buiar. This vague indication to a subdivision of the lateral 

 mandibular plates, about which I dåre not pronounce any 

 definite opinion, before I get better material, reminds one of 

 the condition of the Spoonbill, about which the same un- 

 certainty prevails, as is stated above. The case is, however, 

 doubtful, the more so, because the eventual subdivision is not 

 indicated basally at the hindmargin of the rhamphotheca 

 where it, according to a conclusion per analogiam from other 

 birds, ought to be best developed. The likeness in structure 

 between the bilis of Phoenicopterus and Platalea gains im- 

 portance because it presents itself in two bilis which are 

 both in such a high degree specialised without the likeness 



