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The bones and muscles of the crus and pes of the grey kangaroo are described and illustrated. The hopping of grey kangaroos is also described. The morphology of the musculo-skeletal elements of the crus and pes, together with muscle weight distribution in the pelvic limb, are discussed in relation to hopping. Several errors in the literature on the kangaroo locomotor apparatus are identified.

Maturing patterns of carcass muscle, bone and fat were established using dissection data from 20 large mature size strain and 19 small mature size strain Merino rams. The rams were fed a pelleted ration soon after weaning and individual rams from both strains slaughtered at 6 kg increments in live weight from 18 kg to maturity at 116 and 91 kg for the large and small strains respectively.Composition of mature rams of both strains was similar for the proportion of muscle and bone but there was a slightly greater proportion of fat in the larger strain.The progress of each carcass tissue to maturity was assessed relative to progress of shorn full live weight to maturity. Maturing patterns of the three carcass tissues were not significantly different in the two strains. Muscle and bone were early maturing relative to live weight and fat late maturing.The composition of the large and small mature size strains at the same live weight and at the same proportion of maturity was predicted from the maturity patterns of the carcass tissues and the composition of the mature rams. At the same live weight the large mature size strain had a greater proportion of bone and a smaller proportion of fat than the small mature size strain. At the same proportion of mature live weight, differences between the strains in proportional composition were reduced, and the large mature size strain had slightly more fat.Some guidelines for comparison of strains of animals of different mature size are developed.

SUMMARYEighty-two Merino sheep from birth to 517 days old were dissected into individual muscles. A system of overlapping growth coefficients was used to classify the growth patterns of 96 muscles and nine muscle groups. The relative size of muscles and groups at birth and one year are expressed as percentages of total half-carcass muscle weight.Some differences were noted from the previously recorded growth patterns of bovine muscles. The groups of muscles in the proximal part of the pelvic limb and those surrounding the spinal column were relatively faster-growing in sheep than in cattle.The patterns of the muscle groups are discussed relative to their function and it is shown that the patterns of growth of muscles within some groups are markedly different from the pattern of the whole group. This is most apparent in those groups with complex functions, and it is clear that anatomical grouping of muscles and functional grouping of muscles will be similar only in those regions of the body with relatively simple actions.