The entire collection of Wenlock fossils made by T. W. Fletcher, Esq., which is now in the Woodwardian Museum, affords unsurpassed facilities for studying the material on which a large number of species of trilobites were founded. Particularly is this the case with those of the genus Lichas, and a recent examination of the types and other specimens which Fletcher used in writing his paper “Observations on Dudley Trilobites” (Q.J.G.S., 1850, vol. vi, pp. 235–239, pls. xxvii and xxvii bis) has led me to make the following notes upon them. I have also had the privilege, through the kindness of Dr. Arthur Smith Woodward, F.R.S., of examining the specimens in the British Museum (Nat. Hist.), Cromwell Road.