334: COSTA RICAN EPIGOMPHUS (oDONATA) 



Each lateral ocellus on the summit of an elevation a little nearer to the 

 mesal margin of the adjoining eye (.21 to .28 mm.) than to the mid-dorsal 

 line of the head (.35 to .42 mm.). Meso-caudad of each ocellus and on the 

 elevation is a ridge or wall, subparallel to the ocellar margin, which rises 

 almost, but not quite, as high as the ocellus itself, its crest rounded, the ridges 

 of the right and left sides connected on the mid-dorsal line so that in dorsal 

 view they present the appearance of an inverted W, the angles of wliich are 

 rounded in some specimens; there is some tendency to prolong this ridge 

 on the lateral side of the elevation, as in siihohtusus, but it is not as strongly 

 manifested as in that species where the ocellar elevations are lower. Eleva- 

 tions of the right and left ocelli separated by a depression wliich, in posterior 

 view, is about as deep as one-half of the height of either elevation. 



9 . Vertex similar to that of the d', the distance of the lateral ocelli from 

 the mid-dorsal line of the head a little greater (.49 mm.) in some, the depres- 

 sion between the two elevations deeper in some. 



Vulvar lamina .77 to .84 mm.-- long, reacliing to half of the length of the 

 lateral margin of segment nine, bilobed in the apical .46 (average of 7 9 , 

 range .42-.58, cf. page 330, antea) of its length, interval between the 

 lobes triangular. 



cf and 9 . Pale color on the dorsal surface of the frons separated into 

 right and left spots. 



Metepimeron with a dark brown band on or near its ventral margin, parallel 

 to, but separated from, the brown band, of the second lateral suture by pale 

 green or yeUow of more than its own width; absent in the two alcoholic 

 females (otherwise well preserved as to color) and indistinct in some of the 

 dry specimens of the same sex. 



Abdominal segment two with a mid-dorsal, longitudinal, yellow stripe 

 for more than half the segment's length, reaching or not reaching the extrem- 

 ities of the segment, bordered on each side by brown; three to six chiefly 

 ochraceous, blackish brown in the apical fourth, less defined in the 9 ; seven 

 paler, green or yellow, in the anterior three-fifths, blackish brown in the 

 remainder; eight to ten blackish brown, sides yellowish inferiorly in the cT, 

 indistinctly so on eight in the 9 . 



Abdomen, cf , 38 to 41, 9 42 to 46; hind %ving, d', 34 to 3.5, 9 , 37 to 40 

 mm. 



Type. — cf ; Turrucares, Costa Rica, August 14, 1909, taken by 

 P. P. Calvert. Allotype.- — 9 ; same locality, date and collector. 

 Paratopotypes. — 3 cf , 6 9 ; all as listed aiitea, page 325. 



The specific name proposed alludes to the greater degree of 

 resemblance in the vertex and occiput of the two sexes than pre- 

 vails in the other Costa Rican species here treated. 



^^The measurements here and elsewhere in this paper for the vulvar lami- 

 nae are made by eye-piece micrometer with a Zeiss binocular microscope, 

 paired oculars 4, objectives F 55. 



