480 PROCEEDINGS OF THE ACADEMY OF [Oct., 



have a mean annual temperature of 25°-20° C. and a yearly rainfall 

 of more than 3000 mm.," the former, however, at an altitude of 335 

 metres as against 720 for Zapote. They have yielded respectively 

 26 dry season species and 17 wet season species; each has 6 endemic 

 species {i.e., restricted to Mexico and Central America), one of which, 

 with 7 non-endemic species, is found at both localities. 



The single locality in all Mexico and Central America which has 

 furnished the greatest number of species of Odonata is Atoyac, in 

 Vera Cruz — 68. At least 59 of these were taken in April and May (the 

 specimens of the other 9 are undated), and of these 59, 17 are endemic 

 in Mexico and Central America. If we may judge from the rainfall 

 figures published for the nearest point, Cordoba,^^ April and May, while 

 not a part of the wet season in its stricter sense, may have a precipi- 

 tation of 29-101 mm. and 77-233 mm. respectively, the total for the 

 3^ear being 2600-3200 mm. On investigating the seasonal records 

 for the 17 endemic species at other localities, it appears that they are 

 by no means always confined to one limited portion of the year. 



Gualan, Guatemala, lies in the rainfall zone of less than 1000 m.^^ 

 The only rainfall records from anywhere in the vicinity appear to be 

 those of Teculutan, Department of Zacapa, the monthly figures for 

 1902, from January to December respectively, being 1, 0, 1, 95, 70, 361, 

 ?, 38, 83, 164, 17 and 2 mm.^'o Mr. Wilhamson collected 39 species at 

 Gualan in Januar}^, 1905, 7 of which are restricted to Mexico and 

 Central America. At Los Amates, lying in the rainfall zone of 1000- 

 2000 mm., in the same month and the following February, 35 specief:( 

 were obtained, 6 being endemic in our district. At Puerto Barrios, 

 whose measured precipitation for three years, 1894-6, is 3096 mm., 

 with no month below 50 mm.,^"^ 33 species were procured in December, 

 1904, and February and March, 1905, 7 of these being confined to 

 Mexico and Central America. Gualan has a well-marked dry season, 

 which is much less distinct at Los Amates and absolutely, but not 

 relatively, absent at Puerto Barrios. Of the endemic species, three 

 taken at Gualan (Argia tezpi, A. pipila, Pseudoleon superbus), three 

 at Los Amates (Neoneura amelia, Protoneura remissa, Orthemis hiolleyi), 

 and four at Puerto Barrios {Hetcerina miniata, Argia gaumeri, Neo- 

 neura paya, Protoneura amatoria) were not taken at either of the other 



" Sapper, Petermann's Mittheil., XLIII, map, 1897. 



2» For 1861-3, Nieto, Bolet. Soc. Geog. Estadist. Mex. (1), X, pp. 484 et seq., 1864. 

 " Sapper, I.e., 1897. 



2"Lottermoser, Meteorol. ZeiLschr.. XXIII, pp. 237, etc., 1906. 

 '^Sapper, Petemianns Mittheil., XLIll, pp. 117 et seq., 1897; Meteorol. Zcit- 

 schr., XIV, p. 235, 1897. 



