Wesché employed the relative length of the trumpets to the length of the thorax and the shape of the openings of the trumpets in drawing up a Key to the Pupae of West African Culicidae (Bull. Ent. Res., i, pp. 18–19). Howard, Dyar and Knab in their valuable monograph “ The Mosquitoes of North and Central America and the West Indies ” (Vol. i, pp. 102–103) state that in their experience too much has been made of the difference between the pupal trumpets of Anopheles and Culex; the variations in the shape, size, and length of the breathing trumpets between different species are numerous, they say, but “ furnish no characteristics which are diagnostic of genera or larger groups.” They consider that there are intermediate forms and that differences between species are frequently more striking than between genera themselves. They remark also that this may equally well apply to the differences in shape of the pupal paddles, admitting, however, that “ there is a striking difference between the two tribes Culicini and Sabethini ” as regards the paddles for “ In the Culicini the paddles are large, broad and rounded in outline; they are strengthened by a stout longitudinal midrib which bears a spine or seta apically.