330 COSTA RICAN EPIGOMPHUS (oDONATa) 



Mention may be made here also of two abnormalities noted in the wings 

 of the present forty-six individuals: no true pterostigma exists in the left 

 front wing of the female of E. tumef actus from Guacimo; an incomplete 

 curved cross-vein exists in the basal cell R+M in the left hind wing of the 

 male of E. quadracies from Rio Chirripo, of July 19, 1915. 



The genitalia of the second abdominal segment of the male of 

 E. suhsimilis are shown in PI. XIII, fig. 4. I have ex- 

 panded these organs in suhohtusus 1 cf , tumef actus 2 d^, quad- 

 racies 1 cf , verticicornis 1 cf , and cameJus 1 cf, and compared 

 them with those of subsimilis and have found no differences other 

 than in the size of the first hamule. The form of these organs, 

 therefore, may be considered as a generic character. 



There is little difference also in the vulvar laminae of the fe- 

 males as they resemljle that of E. llama of Bolivia^^, but with the 

 interval between the lobes triangular rather than quadrangular. 

 Taking the six Costa Rican species of which I have females, the 

 apices of the lobes reach to from .4 to .65 of the length of the 

 lateral margin of abdominal segment nine, and the lamina is 

 bifid in the distal .4 to .62 of its length. Details are given pos ea 

 under each species, but I believe that the range of variation in 

 these dimensions is partly, perhaps largely, due to differences 

 in the drying of specimens. 



Dr. Ris, after describing the structure of the posterior abdominal 

 segments of the female of E. ohtusus from Peru as typical of the 

 genus, adds: "Die sehr eigenartige Bildung erweckt die Vermu- 

 tung, dass die Eier in engen Spalten abgelegt werden (vielleicht 

 Zwischen die Blatterbasen der Bromehaceen, wie bei Mecisto- 

 gasterf)."^^ On looking through my field notes made in Costa 

 Rica the only reference to oviposition of Epigomphus which I 

 find is in connection with E. suhsimilis at Turriicares, on August 

 14, 1909, and is as follows: "Epigomphus oviposits unaccompan- 

 ied by cf ; its eyes deep blue above in life.'' In the absence of 

 mention of any pecuhar ovipositing habit, I infer that Epigom- 

 phus then and there dropped her eggs in water as most North 

 American Gomphines do. I can not recall any details of the 

 observation to which this note refers. 



From two females of E. suhsimilis at Turru cares eggs were 

 obtained and from them larvae were reared through at least 



'*See fig. 3, pi. viii, Ent. News, xiv. 



'■'Archiv f. Naturges., 82 Jahrg., Abteil A, 9 Heft, p. 153. 



