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Zoological Society : — 



the discovery of two remarkable powder-down patches which, it will 

 be remembered, I stated on a former occasion * I had failed to find 

 in the living bird. 



Upon removing the skin from the body of this bird, I was so struck 

 by its close resemblance to the Herons, that I immediately killed a 

 Heron and removed its skin also, in order to form a fair opinion by a 

 close comparison of all the parts of these two birds. The exact 

 form of the body and limbs was most remarkable ; the structure of 

 the hind toes (upon which so much stress has been laid) was alike, 

 these turning backwards, forwards, or sideways in both species. The 

 head and neck, however, of Balceniceps, when compared with the same 

 })arts of the Common Heron, present some very considerable differ- 

 ences. These differences consist, first, of the much larger head, and 

 consequently stronger neck, in Balceniceps as compared with the 

 Heron. Doubtless these modifications have reference to the food and 

 the mode of obtaining that food. Many illustrations can be found 

 of similar modifications ; I may refer to one in the group under con- 

 sideration, which results from the comparison of Cancroma with 

 Eurypyga, and which presents, perhaps, the most extreme modifica- 

 tion in the form of the bill in two birds of the same family. 



As far as I was able to examine the viscera of the Balceniceps, I 

 could discover nothing that would lead me to doubt its Ardeine 



Fig. 1. 



affinities ; the stomach, liver, intestines, &c., of the two birds ap- 

 peared exactly to correspond in structure and arrangement. 



• See * Annals ' for April 1861, p. 326. 



