In a paper published with Warburton in 1909 (Parasitology, ii. 70–76, Figs. 17–26), I described and figured a number of abnormalities observed in ticks of which the most remarkable were two specimens, Boophilus decoloratus ♂ and Rhipicephalus sanguineus ♂ (Figs. 22, 25 and 26), showing two ani together with a duplication of the adanal shields; in the Rhipicephalus duplication was more pronounced in that a subcircular spiracle was present posteriorly in the median line; the Boophilus exhibited two caudal spines. The other specimens figured were Hyalomma aegyptium ♂ and Boophilus australis ♂ (Figs. 18 and 21) which showed underdeveloped adanal plates on the right side. All of these specimens were found attached to a host.