242 SMITHSONIAN MISCELLANEOUS COLLECTIONS [voL. 48 
second segment or slightly shorter, cylindrical, straight-sided and 
truncate at the tip. The apex has a surrounding crest of scales and 
short spines which indeed gives it, superficially, the appearance of a 
broken joint, but close examination shows the tip, within the sur- 
rounding crest, to be densely clothed with metallic scales—a condi- 
tion which would certainly not obtain on the insertion of an- 
other segment. This error was already committed by Macquart, 
who credits the female Megarlunus hemorrhoidalis with five-jointed 
palpi and explains in a foot-note: “Un individu 9 du muséum 
dhistoire naturelle a le 5.° article des palpes brisé, de sorte qu’il 
nest pas possible d’en déterminer la longueur.”' In the figure 
of the female head on Pl. I he shows the four actual segments in 
heavy outline, and, dotted in, the supposed fifth segment. Dr. Lutz, 
in Bourroul’s work, which we know only from the extracts in Blan- 
chard,” seems to have recognized the true condition. He erects for 
the forms in which the female has the terminal segment of the palpi 
long, sabre shaped, the genus Ankylorhynchus, including M. viola- 
ceus, M. trichopygus (Wied.) and a new species, A. neglectus. In 
the two sexes the relative proportions of the corresponding palpal 
segments do not agree. These relative proportions appear to serve 
very well in the separation of the two forms (at least in the male) 
treated. by Lynch-Arribalzaga* and subsequent authors as M. sepa- 
ratus and M. hemorrhoidalis but offer no easy distinctions in the 
closely related forms here described. 
It should be noted that all the old world Megarhini of which the 
structure of the female palpi has become known have been referred 
to Toxorhynchites, while all the American forms belong to Mega- 
rhinus and Ankylorhynchus. The only exception is the Culex 
splendens of Wiedemann from the East Indies, which Theobald has 
definitely referred to Megarhinus*; however nothing has appeared 
in print to throw light on the structure of the female palpi in this 
species. According to Theobald there are no characters to separate 
the males of these genera. “We will not say that these genera should 
be merged, for good characters may yet be found to separate the 
males as well, but certainly they do not deserve sub-family rank. 
We have already expressed our views regarding the use of the 
length of the palpi for primary division in the Culicide. * <3 
1Diptéres exotiques, v. I, p. 32 (1838). 
2Les Moustiques, 1905. 
3 Revista del Museo de La Plata, v. 1, pp. 376-377; v. 2, pp. 133-134 (18901). 
4Genera Insectorum, 26 fascicule, p. 13 (1905). 
5Journ. N. Y. Ent. Soc., v. X1v, pp. 171-172. 
