Prof. J. Reiuhardt on the Affinities 0/ Balgeniceps. 145 



The Cancroma does not, in my opinion, represent a peculiar sub- 

 family ; it is in every respeet a Night Heron, gifted with a very sin- 

 gular beak. The plumage, the feet and their serrated middle cla^vs, 

 and, further, the colour, manifest the affinity. Even in the bill, ano- 

 malous as at first sight it may appear, a minute examination will 

 enable us to recognize the beak of a stout-billed Night Heron {A. vio- 

 lacea, for instance), strongly modified, it is true, in shape, but still 

 exhibiting many of the essential characters. To the beak of the Balce- 

 nlceps, on the contrary, it seems to afford only an analogy (and not even 

 a very strong one), bat no true affinity. Its flattened form, and the 

 slender and pliable branches of the lower jaw, prove, in my opinion, 

 that the beak of the Boatbill is calculated rather to be a very capa- 

 cious than a very strong one ; whilst the bill of the Baleenicejjs, being 

 higher than broad, evinces an extraordinary strength in almost every 

 feature, but especially in the powerftd hook in which the culmen 

 terminates. In the Boatbill there is no such hook, but the upper 

 mandible is provided with the usual notched tip of the Night Herons, 

 not separated from the sides of the bill by a well-marked groove, as 

 is the hook of its presumed kindred ; and if we carry on the com- 

 parison farther, we shall find that the lower jaw does not offer the 

 truncated apex characterizing this part in the Balccnicejis, and being 

 indeed the consequence of the shape of the hook. The different 

 form of the nostrils and the different size and extent of the nasal 

 groove afford other notable points of diversity between the two 

 birds ; and though the skin of the throat may be dilatable in a certain 

 degree in the living Balceniceps, I should not think that this bird 

 possesses a true pouch like that of the Cancroma. At all events, the 

 fact of the mentnm being very thick-feathered throughout two-thirds 

 of its length induces me to doubt it ; and the stout and ajiparently 

 little-})liable under jaw seems also to make it not very probable. 



It must be conceded that the BalcEiiiceps approaches much to the 

 Cancroma in the general structure of the feet ; but it has not, like 

 this bird, a pectinated middle claw ; and this circumstance affords, 

 in my opinion, a strong warning not to class it with the Boatbill, as 

 this peculiar serrature never fails in any member of the Heron 

 tribe. 



As to what relates to the nature of the plumage the Balceniceps 

 differs also, in not unimjjortant jioints, from the Cancroma, the downy 

 part of each feather being proportionally larger, and genuine down 

 being intermixed in considerable quantity among the feathers, as in 

 Leptoptilos, while in the Cancroma and the Herons there is hardly 

 any down at all amongst them : moreover the hyporhaehis is well 

 developed in the last, but very small in the Baheniceps, which also 

 in this point seems to adhere to the Storks, in certain species of which 

 it is even entirely wanting. The distribution of the feathers on the 

 body (the pterygose) cannot be accurately studied on a stuffed skin ; 

 therefore 1 am not able to give any sufficient account of it in the 

 Balceniceps ; but even now I think I may say that the pterygose 

 of this bird, when miinitely examined, will ])robably show notable 

 differences from that of the Boatbill. It especially appears that the 



