PHILIP A. MUNZ 17 



also a narrowing and sharpening of the quadrangle distally. Peti- 

 olation does not proceed very far, ne\er to the level of the arculus. 



The Lestoidinae 



Air. Tillyard (1912a) described as a new genus a very peculiar 

 form which he called Lestoidea (fig. 45) and for which he proposed 

 a new legion of the same name. This remarkable insect has de- 

 cided Lestine affinities in the location of the base of Ms and R,, but 

 has the vein Cuo reduced to a cross-\ein and Cui but one cell long. 

 Yet in addition to the above characters it is distinguished from all 

 Protoneurinae by the presence of two sectors between M, and Mj^. 



The decrease in length of Cui and Cu2 is one of the most extreme 

 tendencies in specialization occurring in the Zygoptera and its 

 origin in the various groups is an interesting parallelism. As al- 

 ways happens when Cuo is thus reduced MA is straightened and the 

 quadrangle ends squarely. The retention of the two sectors be- 

 tween Ml and M,,, is rather remarkable, in view of the fact that all 

 others are gone and that in none of the Lestinae are there any long 

 sectors between these two veins. Lestoidea must therefore have 

 arisen from some rather ancient form and is distinct enough to 

 merit a legion for itself or in the system here used, a subfamily. 



The Megapodagrioninae 

 Here are included the genera ordinarily considered as belonging 

 to the legion Podagrion of de Selys; this is the group which leads 

 to the higher members of the Coenagrionidae. The genus most 

 distinct from the others is undoubtedly Thaiimatoneiira (fig. 51), 

 which has been given much attention by \-arious workers. Afc- 

 Lachlan (1897) and Foerster (1909) referred it to the Agrionidae; 

 Needham (1903a) spoke of its affinities to the Pseudostigmatinae 

 and Calvert (19 13) placed it in the Megapodagrioninae. All 

 agreed that it was an intermediate form. The safest course to 

 follow seems to be to leave it in the Megapodagrioninae, but to call 

 attention to the fact that it shows an undoubted approach to the 

 Pseudostigmatinae. It is unquestionably one of the Coeuagrion- 

 idae although it does have more than two antenodals. Neuro- 

 lestes (fig. 62), Trineuragrion {{\g. 54), and often Neuragrion have 

 three antenodals as the normal condition, so that the old idea of 



MEM. AM. ENT. SOC, 3. 



