Summary. The pectoral girdle and fore limb of Equus and Dasypus are compared. It is shown that the shoulder muscles of the horse have a small mechanical advantage (1/13 for the m. teres major) and are therefore adapted to produce rapid movements of the limb; these muscles in the armadillo have a larger mechanical advantage (1/4 for the m. teres) to produce slower movements, while exerting a greater force. The broad scapulae and short legs of fossorial mammals are adaptations producing powerful movements of the foot, usually with strong abductor action. Aquatic mammals show similar modifications, though without the emphasis on abductor movements. The high, narrow scapulae and long legs of cursorial mammals are explained as adaptations to speed, though the detailed arrangements by which this is achieved differ in cursorial ungulates and carnivores. The sharp angles at the ends of the vertebral border of the scapula in cursorial ungulates provide pints of insertion for two parts of the m. serratus, which act as antagonists in the fore‐and‐aft movement of the shoulder. Similarly in the dog, and probably all cursorial carnivores and lagomorphs, the sharp vertebro‐axillary angle affords a point of insertion for the posterior digitations of the m. serratus. The mechanical adaptations of the olecranon process and the m. triceps are described. The structure of the vertebral column and axial musculature is shown to depend upon gait. Two types of gallop, the horse gallop and leaping gallop (e.g. dog) are analysed and the association between gait and structure described. The mechanics of gaits are discussed in an appendix. The extensor muscles from the pelvis to the femur fall into two groups, an iliac group adapted to rapid extension of the thigh, and an ischio‐pubic group adapted to slower but more powerful thigh extension. The relative proportions of the two regions of the pelvis vary according to the gaits adopted. In cursorial ungulates the ilium is long and the ischio‐pubic region short, whereas in aquatic mammals the latter region predominates. The lengths and cross‐sectional areas of the bones of the hind limb are shown to be correlated with gait in aquatic, cursorial (leaping gallop and horse gallop), saltatorial and graviportal mammals.

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Summary. A detailed account is given of the anatomy of the skeleton and dentition of Potamotherium, the first known otter, from Upper Oligocene lacustrine deposits in Allier, central France. Almost all parts of the skeleton are represented: the bones are plentiful and well preserved, displaying many aquatic adaptations. The taxonomy of the Lutrinae, the stratigraphy of the deposits containing Potamotherium and their associated fauna are briefly discussed in the introduction. Study of the dentition includes consideration of milk teeth. Potamotherium is the only lutrine retaining the second upper molar and the dentitions, both milk and permanent, are rather more complex than those of present day lutrines, though basically very similar to Lutra: the differences are interpreted taxonomically but no functional explanations are possible. The description of the skull bones is outlined and the structures transmitted by the cranial foramina interpolated. Detailed study is centred on the brain, ear and nasal region. The pattern of the cortical convolutions is mapped, and the ratios of brain weight to body weight in various lutrines are compared. The petrosum reveals details of the semi‐circular canals and cochlea, and two of the ossicles are described: an attempt is made to interpret auditory perception. Preservation of maxillo‐ and ethmo‐turbinals, together with the olfactory lobes of the brain leads to an analysis of the nasal region and its functions. The mechanics of jaw movements are discussed and these considered along with the dentition suggest the likely feeding habits. The anatomy of the vertebral column, ribs and sternum is described in detail. The main factors influencing locomotion are discussed and comparisons made with living carnivores. The poise of the neck, arching of the back and length of the tail are each considered. The varying position of the zygapo‐physes are correlated with the degree of flexibility of the back and certain characters of the ribs are shown to be adaptations to aquatic breathing. The anatomy of the pectoral girdle and fore limb includes discussion of the main muscles. The mechanical bases of the limb adaptations are explained, and these compared with fully aquatic and non‐aquatic species. The rotary movements of the manus are correlated with its use in land and in water. The study of the pelvic girdle and hind limb reveals that most bones have different proportions from those of terrestrial carnivores; this effects the mechanics of muscle actions, enabling aquatic movements to be performed more effectively. Prom the shape of the pelvic girdle the probable size of the litters is predicted. The knee joint, the patella, the muscles to the pes and the length of the metatarsals are among the features discussed in the determination of the functions of the hind limb. In conclusion the mode of life and probable appearance of Potamotherium are considered. On land it must have closely resembled Lutra, while in the water this abundantly successful lake‐dweller was a powerful swimmer.

Soldiers undergo regular physical testing to assess their functional capacity. However, current physical tests, such as push-ups, sit-ups, and pull-ups, do not necessarily assess job-specific physical capability. This article assesses the utility of generic predictive tests and a task-related predictive test in predicting performance against four job-critical military manual handling tasks. The box lift and place test was found to be the superior predictor in performance of four job tasks; a pack lift and place (R(2) = 0.76), artillery gunner loading simulation (R(2) = 0.36), bombing up an M1 tank simulation, (R(2) = 0.47) and a bridge building simulation (R(2) = 0.63). Pull-ups and push-ups were poor predictors of performance in the majority of job tasks. Although the box lift and place had a larger correlation with the artillery gunner loading task than the generic assessment, it only accounted for 36% of the variance, indicating that a task simulation may be more appropriate to assess soldiers' capacity to perform this job task. These results support the use of a box lift and place rather than generic fitness tests for the evaluation of military manual handling tasks.

Summary The ‘Turkana Grit’ deposits of northern Kenya are a thick sequence of immature arkosic sediments of pre-Plio-Pleistocene age. Originally described by Murray-Hughes in the 1930s, these sediments have been variously considered as of either Mesozoic or Miocene age by subsequent authors. These extremely immature, tectonically controlled sediments clearly reflect intense local deformation; their age is of considerable interest, as they clearly signal the onset of significant tectonic activity in the central sector of the East African rift. A regional survey of the Turkana Grits as currently known, coupled with recently available information from the hitherto unmapped Kajong area in the SE Turkana basin, clearly indicates that these sediments represent two distinct episodes of local tectonism and deposition. On the basis of available radiometric and biostratigraphic evidence, the earlier of these episodes appears to be of Cenomanian-basal Palaeocene age, while the later episode dates from the mid-Miocene. These observations suggest that significant tectonic activity in East Africa commenced in the late Mesozoic rather than—as generally assumed—in the mid-Cenozoic. The earliest (late Mesozoic) episode of clastic deposition in the Kajong area was initially controlled by a set of major E-W trending transform faults; these deposits are primarily preserved in associated fault-wedge basins. The documentation of a major transform element in the Kajong area has important implications for the early development of the African Rift as a whole. We suggest here the possibility that the enigmatic distribution of the late Mesozoic rift sediments—which are restricted to the southern sector of the Western Rift and the northern sector of the Eastern Rift—reflects the fact that the original late Mesozoic rift consisted of a single graben. The southern and northern portions of this graben have been subsequently displaced by a major E-W trending dextral transform system, extending some 500 km from the SE Turkana basin to the present northern termination of the Western Rift on the Uganda-Sudan border.