A 1931 article from The Melliand Textile Monthly reporting a microscopic survey of alpaca and llama fibers taken from a 100-bag shipment received by a Philadelphia mill. It describes fiber structure (smooth surface, little scale, medullae, pigment granulation) and compares it with sheep's wool. It also gives ether-extractable grease and dirt content and fiber diameter distributions for seven color sorts in two tables. Average diameters are compared with Government Standard Wool Tops grades, concluding that alpaca/llama averages 26 to 36 microns, roughly equal to 58's down to 46's wool.