172 Mr. K, J. Morton on a new genus of Odonata. 



Prof. Calvert in his recent paper : * " The Fossil 

 Odonate Phenacolestes, with a discussion of the venation of 

 the legion Podagrion, Selys," gives a synopsis of the 

 venational characters of this legion. The new genus 

 would fall under — 



AA, — M^ separating from M 1 + 2 at the sub-nodus, only two 



antenodals, Rs beginning distad to the sub-nodus. 

 VV. — Area posterior to Cu'^ with one row of cells, one cubito- 

 anal cross -vein. 



For Cliorismagrion a new rubric preceding Chlorolestes 

 is required, based on the absence of the basal side of the 

 quadrilateral and the absence of supplementary sectors. 

 In regard to these latter it may be well to call attention to 

 the minute rudiment at the edge of the wing between M^ 

 and Rs in the new genus. 



The opportunity is suitable for giving a good wing 

 photograph of Hemijphlehia, which Dr. Ris has also kindly 

 supplied, as none of the existing figures seems to give a 

 direct photographic representation of the wing. In sending 

 this photograph he points out the existence of a minute 

 cross-vein between A* detached from the anal margin and 

 this margin, just at the Cuq. This detail, which Dr. Ris 

 says is not known to him in any other Agrionid, is so 

 minute in the photograph that it may be lost in repro- 

 duction. In one of my specimens it is more distinct, but 

 it does not appear to be constantly present, and Tillyard's 

 figure truly represents in this respect the condition of 

 another example in my collection. 



* Proc. Academy Nat. Sciences of Philadelphia, 1913, pp. 225-272. 



Explanation of Plate IX. 



Fig. 1. Wings of Cliorismagrion risi (nat. length of h.-w. 22 mm.). 



2. Wings of Cliorismagrion risi, basal part more enlarged. 



3. Apex of abdomen of Choristnagrion risi, from above. 



4. Wings of Hemijihlebia mirabilis from Alexandra, Victoria 



(nat. length of h.-w. about 11 mm.). 



