^"^'i ^'^1 SiiUFELDT, Material for a Study of the Megapodiidce. i8q 



a few other muscular lines. At the distal extremity the condyles 

 are very bulk}-, and widely separated anteriorly by a wide and 

 deep intercondylar valley. Posteriorly, the rather shallow 

 " popliteal fossa " is unequally divided by a low, submcdian 

 ridge, which terminates above the external condyle. On the 

 external surface of either condyle occurs, near the centre of each, 

 the usual pit for insertion of the lateral ligaments of the knee. 



When the collector roughed out this specimen of malco lie 

 removed, through an oversight, the patellce, with the tendons in 

 which th(>y occur ; the consequence is that I cannot describe them 

 here. That this mound-bird possesses these sesamoids there 

 can hardly be any doubt ; for all bird forms, having both near 

 and remote relations to it, have them — a fact well-known to 

 ornithotomists. All true GalUnaceous fowls possess patella*. 



Passing to the bones of the leg, next to be described is the tihio- 

 taysus, which is, as in the femur, a bone fashioned along rather 

 massive lines, as well as being one of good length. From the 

 highest point on the cnemial crest to the lowest point on the 

 distal condyles — -either one of them — it measures 13. i cms. The 

 summit is extensive and quadrilateral in outline, exhibiting the 

 usual concavities for articulation with the femoral condyles. 

 Anterior to these, the cnemial crest rises but very slightly above 

 the general surface, its superior border being in the transverse 

 line. The inner or " entocnemial crest " extends down the shaft 

 a little over two centimeters, in a direct line with the longitudinal 

 axis of the same,knd there merges with it. Above, it gradually 

 slopes towards the superior cnemial border, to merge eventually 

 into it (fig. 41). The outer or " ectocnemial crest " stands out 

 directly at right angles with the shaft of the bone, which it very 

 soon runs into. Its superior border is thickened, especially its 

 external angle. On the posterior aspect of this proximal end of 

 the tibio-tarsus, the summit of the bone projects over the shaft 

 as a prominent, outstanding ledge. As to the shaft of this bone, 

 it is perfectly straight, smooth, and unmarked. It is somewhat 

 flattened in the antero-posterior direction, and a sharp line is 

 continued down it from the lowermost point of the entocnemial 

 crest to a short distance above the condyles. Anteriorly, at the 

 distal end, there is a heavy, osseous " tendinal bridge " spanning 

 the longitudinal groove for the tendons of certain muscles in that 

 region — a feature present in this part of tlie skeleton in a great 

 many birds. 



The condyles are large and otherwise well developed. Pos- 

 teriorly, the intercondylar valley is transversely very broad and 

 notabh- shallow, while in front it is narrow and much deeper. 

 On tlif outer aspect of tliis tibio-tarsus the fibular ridge is low 

 and long : it occupies a large* part of the line in the upper third of 

 the shaft. To its cntirr Irngth the fibula is attached 1)\- a firm, 

 fibrous ligament. 



Turning to the fibula itself, we find it to have a length of about 

 6.7 cms., it being very slender below its articular ridge on the 



