314 MR. F. F. LAIBLAW ON 



9. *Heli^schna uninervulata Martin. 



Heliceschna uiiinervulata Martin, Cat. Coll. Selys, ^schn. pp. 

 163-164 (figs. 165, 168). 



This species, described originally from Borneo, occurs also in 

 Lower Burma. (1 S , coll. E. B. Williamson.) 



10. *HelIjESCHNA siMPLiciA (Karscli). 



Amphiceschna simjjlicia Karscli, Ent. Nachr. xvii. 1891, p. 308; 

 Karsch, Ent. Nachr. xviii. 1892, p. 250. 



Heliceschna simjMcia Karsch, Ent. Nachr. xix. 1893, p. 195 ; 

 Martin, Cat. Coll. Selys, ^sclin. pp. 161-162 (fig. 162). 



11. *AMPHIiESCHNA PERAMPLA Martin, 



Am'phiceschna ferampla Martin, Cat. Coll. Selys, ^sehn. p. 115 

 (figs. 108, 109). 



12. Amphi^schna grubaueri Fdrster. 



Amphiceschna gruhaueri Forster, Insekten-Borse, xxi. (1904) 

 pp. 1-3 (sep.) ; Martin, Cat. Coll. Selys, vEschn. pp. 115-116 

 (fig. 110); Laidlaw, Journ. Straits Branch R. Asiat. Soc. Ixiii. 

 1912, p. 94. 



1 ? . Mt. Batu Lawi, 24. v. 11. 



The arculus in the fore-wings of this specimen is of a primitive 

 character. The upper part is very oblique and readily seen to 

 be formed by M^^g, M^, which separate before M^ is met by the 

 scarcely thickened cross-vein which forms the lower part. 



The upper part of the hinder-wing is much less oblique. 



The costal, subcostal, median, and cubito-anal spaces in both 

 fore- and hinder-wing are opaque, dark brown to a level of about 

 one cell before the arculus ; the anal area of both wings tinged 

 with orange-brown to about the same level. Beyond the nodus 

 the wings are tinged with orange-brown almost to the apex. 



The ventral plate curves vipwards at its apex and carries about 

 8 small irregular spines. Its ventral surface has a deep conical 

 depression to receive the points of the terebrse. 



Abd. 62 mm., h. w. 63 mm. Pt. 2 mm. 



(The measurement given by me {loc. cit.) of 70 mm. for the 

 hinder- wing was an error.) 



13. Tetracanthagyna plagiata (Waterhouse). 



leiracanthagyna plagiata Kirby, Cat. Odonata, p. 94; Krixger, 

 Stettin. Entomol. Zeitg. 1898, pp. 287-288 ; Martin, Cat. Coll. 

 Selys, ^schn. pp. 145-146 (figs. 144, 145). 



1 ^ . Kakus, vi. 13. 



Ris (loc. cit.) suggests that the next species, separated from 

 plagiata on account of the colouring of the wings of the female, is 

 identical with it ; and that l\2}lagiata has two forms of female, one 

 with a costal stripe and transverse band of brown on the wings 



