Published online by Cambridge University Press: 06 July 2012
The following account deals with investigations pursued by the authors during the years 1931 and 1932. Pressure of other and later work precluded the possibility of the results of the investigations being published until this year. It is believed that no recent account of the cuticular-scale pattern of monotreme hairs has been published, and the authors are convinced of the desirability of such a detailed description. When this work was commenced it was intended to be the first of a series of investigations into the scale- pattern of mammalian hairs. Hitherto work in this direction has only taken the form of either a consideration of one species only, or generalisations upon the scale-pattern of a group of mammals. Such generalisations would appear to be often unjustified for the following reasons: In many instances they are based first upon an insufficient number of observations along the length of each fibre, and secondly upon a technique of preparing the fibres for examination which would seem to be inadequate for accurate vision of all the delicate lines marking the boundaries of the scales. Although notable attempts to indicate these boundaries have been made (Hausman, 1920; Glaister, 1931), in the authors' opinion the results have not been satisfactory. Moreover, until Manby's methods, described in previous papers and also in this account, were perfected, there has been no really satisfactory method of photographing cuticular-scale patterns accurately.