One or two errors in “ Mosquitoes of the Ethiopian Region ” have recently come to light, and several new Culicine larvae have been discovered since the first volume was published. I take this opportunity to correct the errors and to indicate the positions which the newly-described larvae should occupy in the keys. I have not seen most of these larvae and have inserted them in the keys solely from the descriptions.

A number of the mosquitos of which I described the larvae in Vol. I of the monograph were incorrectly determined, but Edwards has already pointed out these misdeterminations (in Vol. III) and I have not thought it necessary to mention them here.

At the request of Mrs. G. R. Cunningham van Someren (formerly Miss E. C. C. Macdonald), I have added her description and figure of the larva of Aëdes adersi and her description of that of Culex adersianus as an appendix (see p. 178).