X. On a group of varieties of the muscles of the human neck, shoulder, and chest, with their transitional forms and homologies in the mammalia

The muscular varieties described by the author in his paper comprise theoccipito-scapular , thelevator claviculœ , and thecleido-occipital , among the muscles which elevate the scapulo-clavicular bone-arch ; thesterno-scapular , thesterno-clavicular , and thescapulo-clavicular , of those which depress it ; and thesupracostal , placed upon the upper part of the thorax.