DRAGONFLIES OP BURMA AND SIAM— WILLIAMSON. 291 



of head, thorax, and legs, and form of occiput. From decemlineatus 

 by coKh' of head, thorax, legs, and abdomen. 



Genus LEPTOGOMPHUS De Selys. 



The ten species referred to tliis genus, some with considerable 

 question, are all members of the oriental fauna; four have been 

 recorded for Burma. The following notes gathered from the litera- 

 ture of the subject may be of value in separating the species: 



L. assimilis Kriiger. Tentatively proposed hy Krtiger for Su- 

 matran specimens very close to lansbergei. The size is somewhat 

 smaller, the stigma somewhat shorter than the figures given by De 

 Selys for lansbergei; there are 2 additional postoccipital spines; the 

 upper lip has 2 large instead of 2 small yellow spots; the prothorax is 

 more yellow, and the anterior femora are yellow beneath. 



L. gestroi De Sel3^s. Burma and Tonkin. AbdomeU; male 40-42 

 mm., female 39 mm. hind wing, male 34-35 mm., female 35 mm.; 

 antenodals, front wing 15-16; postnodals, front v/ing 11; basal ante- 

 nodal of second series present in 4 wings. 



L. gracilis Kriiger. Sumatra. Abdomen without appendages, 

 male 27-28 mm., female 30 mm.; hind wing, male 23-25 mm., 

 female 25 mm.; antenodals 12-13; postnodals 10-12; basal ante- 

 nodal of second series not present; between Mj. ^ and M^ 4 or 5 cross 

 veins in front wing, 3 or 4 in hind wing. Kriiger regards nietneri 

 and gracilis as not congeneric with sempei'i. 



L. inclitus De Selys. Burma and Moolai. Abdomen, female 36 

 mm.; hind wing, female 32-33 mm.; antenodals, front wing 14-19; 

 postnodals, front wing 9-11. 



L. lelantanensis Laidlaw. Malay Peninsula. Abdomen, 31 mm.; 

 hind wing 26 mm.; antenodals, front wing 11, hind wing 10; post- 

 nodals, front wing 10, hind wing 10; basal antenodal of second 

 series wanting. Laidlaw's description and figure of venation and 

 his description of male appendages clearly indicate the genus Lepto- 

 gomplius rather than (lomplms, to which he assigned the species. 

 His figure represents 3 cross veins between Mj.., and M^ in front 

 wing and 3 or 4 in hind wing. 



L. lansbergei De vSelys. Java and Sumatra (see L. assimilis above) 

 Abdomen, female 39 nnn.; hind wing 35 nun.; antenodals, front 

 wing 17-18; postnodals, fj-ont wing 13 (De Selys). Al)domen with- 

 out appendages, male 36-37 mm., female 36 mm.; hind wing, male 

 29 mm., female 33 mm.; antenodals, front wing 14-16; postnodals, 

 front wing 11-12; basal antenodal of second series present; between 

 Mj 3 and M^ 4 or 5 cross veins in front wing, 2 or 3 in hind wing 

 (Kriiger). 



