264* PROCEEDINGS OF THE ACADEMY OF [May, 



it is of interest to point out that they are not in their present geo- 

 graphical distribution the nearest Podagrionine genera to Colorado, 

 as none of their species are known from a more northern locality 

 than Colombia ("Bogota")- In the intervening territory are found 

 Thaumatoneura, Paraphlehia, Philogenia, Heteragrion, and Perilestes, 

 and of these four genera the most northern known representatives 

 are Paraphlebia zoe and hyalina and Heteragrion chrysops of the 

 State of Vera Cruz, Mexico.^* 



Professor Cockerell has suggested in correspondence that although 

 the genera allied to Phenacolestes are now Neotropical, they are of 

 northern origin or had northern ancestors. Considering how wide- 

 spread are the living genera of the legion Podagrion, it seems incon- 

 ceivable that their forerunners in the Miocene did not inhabit many 

 other regions than Colorado, The fact that we know them only 

 from Florissant seems to the writer very negative and insufficient 

 evidence on which to found a conjecture as to the place of origin of 

 this group. 



On THE Subfamily Dysagrionin^ Cockerell. 



Preceding his original description of Phenacolestes mirandus, 

 Professor Cockerell proposes a new subfamily of Agrionidse {sensu 

 strictiori) , under the name Dysagrioninse, which he defines as follows.^' 



"Antenodals 2 Subfamily Agrioninae. 



Antenodals 4 or more Subfamily Dysagrioninse." 



The number of antenodals is hardly a character of sufficient impor- 

 tance by itself to establish a subfamily, owing to its variability, and at 

 least three genera come between Professor Cockerell's two divisions. 

 Thus in Thaumatoneura M'Lachn., the number of antenodals varies 

 from 3 to 5, and Neurolestes Selys of Africa and Neuragrion Karsch 

 of Ecuador have three antenodals.^*'" It is not without bearing on 

 the present topic that all three of these living genera, as well as 

 Phenacolestes, are of Selys' legion Podagrion, but if any new taxo- 

 nomic arrangement, whether of "subfamilies" or of "legions," is to be 

 made, the distinctive characters must be formulated in some other 

 terms than those which Professor Cockerell has employed. The 

 tenability of the subfamily Dysagrioninse has also been discussed 



98 Calvert, Biol. Centr. Amer. Neur., pp. 60, 61, 64, 1901. 

 M Bull. Amer. Mus. Nat. Hist., XXIV, p. 60. 



«» Cf. Calvert, Ent. Mo. Mag., XXXVIII [2-XIII], pp. 29-32, 1902, where 

 also the characters of the Agrioninae are discussed. 



