PHILIP P. CALVERT 343 



Dr. Ris has described the vertex of arniatw^ male which lacks 

 the postocellar tubercles.^'' 



Epigomphus tumefactus (PL XIV, figs. 20 to 22.) 



On the dorsal surface of the head of the female there is a dis- 

 tinct parocular groove (prs) along the mesal margin of each eye 

 from the antenna almost to the occiput; it is deepest at its pos- 

 terior end. Between the right and left parocular grooves are 

 three other longitudinal grooves each delimited laterad by dis- 

 tinct longitudinal ridges. The median of these may be called 

 the median vertex groove or sulcus (tnvs) and extends from the 

 frons almost to the occiput; it is wider anteriorly, where it lodges 

 the median ocellus, narrows to its mid-length, thence widens 

 slightly to its posterior end. The other two grooves may be 

 styled paramedian or lateral ocellar sulci (los) and extend almost 

 from the hind margin of the frons almost to the occiput; the 

 ocellus in each groove is situated on the mesal slope thereof. 

 All five grooves are barred from reaching the occiput by a low 

 transverse, posterior, terminal ridge of the vertex (PI. XIV, fig. 21, 

 tr) reaching from eye to eye. 



The female from the Florida Road, of June 3, has a marked 

 superior ocular cicatrix on the right eye at its mesal margin 

 opposite to the ocellus of the same side, a scar which extends into 

 the right parocular groove. In the corresponding part of the 

 left parocular groove there are three or four slight impressions, 

 close together, which may be cicatrices, but there is nothing of 

 the kind on the left eye. 



The occiput has a pair of low transversely elongated tubercles 

 or low ridges (fig. 21, dor) in the middle two-fourths of its dorsal 

 surface, its hind margin is distinctly and narrowly emarginated 

 in the middle and there is a strong tubercle with blunt, rounded 

 apex (pot) on the posterior surface laterad to the level of the 

 mesal angle of the dorso-mesal margin of each compound eye. 



On each side of the rear of the head, at about one-third of the 

 distance from the lateral end of the occiput to the outer surface 

 of the eye is a subvertical ridge (fig. 22, r), on the mesal side of 

 which is a pit {p, same figure) and on the lateral side a distinct 

 subvertical groove (g). From the pit and a wide shallow trough 

 running from it mesad and ventrad extend mesad and dorsad 



30Archiv f. ^laturgesch., 82 Jahrg., Abteil. A, 9 Heft, p. U7. 



TRANS. AM. ENT. SOC, XLVl. 



