10 



Transactions. — Zoology. 



The tibia has a length of 17 - 5in. (445mm.) ; the proximal 

 width is 4 - 6in. (117mm.) ; width of the shaft, T4in. (36mm.); 

 and distal width, 2 - lin. (53mm.). The antero-external surface 

 is slightly rounded. The distal end of the specimen is unfor- 

 tunately partly destroyed, but it shows the extremity to be 

 less expanded than in M. casuarina. From the tibia of 

 Megalapteryx the present tibia differs in being more expanded 

 at the proximal end. 



The femur has an average length of 9 - 8in. (249mm.); the 

 proximal width is 3-3in. (84mm.) ; the width of the shaft is 

 T4in. (35mm.); and the distal width, 3-5in. (89mm.). The 

 popliteal area is but slightly depressed and not well marked off, 

 by which character it can be distinguished from the femur of 

 Palapteryx plena. The head rises slowly ; the linea aspera is 

 fairly well marked, but there is a smooth space between the 

 rough tubercle below the nutrient canal and that on the inner 

 side of the popliteal area. This character distinguishes it 

 from the femora of Mcsopteryx, Palapteryx, and Megalapteryx; 

 the popliteal area is also shorter than in Megalapteryx. The 

 shaft is more curved anteriorly than in A. didiformis, but less 

 so than in Megalapteryx tenuipes (Lydekker). From the femur 

 of M. casuarina it can also be distinguished by being slighter, 

 by having a shorter head, and by not being so expanded 

 distally. 



I append a table of measurements in which are included the 

 leg-bones of an individual skeleton of A. parva,, from a cave at 

 Highfield, near Waiau. It will be seen that this specimen 

 has a longer and more slender femur than A. didiformis, the 

 dimensions of which are taken entirely from North Island 

 birds. This, however, seems hardly sufficient to entitle it to 

 rank as a separate species. 



