TklACANTlIACVNA AND (jVXACANTIIA 3I 



This is the most brilHantly ccjlored of the American G\"nacanthas. In 

 keeping with this it is an especially alert and wary species apparently not 

 at all crepuscular in its habits. Dr. Calvert's male (9) was taken during 

 the day (before 4 p. m.), and at La Fria it \/as observed from about 9 a. n». 

 to 4 p. m. Several were seen but in spite of our best efforts we succeeded 

 in taking only a single male, though two days, after the capture of this 

 single male, were practically given to search for this species. At La Fria 

 the heavy tropical forest north of town covered the nearly level surface in 

 a great unbroken stretch of dense verdure. Through this forest, at the 

 season we collected there, odonate life was widely distributed with no con- 

 centrating at suitable spots such as streams or permanent pools. When 

 odonate life is so scattered in the temperate regions, even where agricultwre 

 or natural conditions permit easy access to all parts of the dragonfly domain, 

 it is ? matter of common knowledge that the capture of specimens is difficult 

 or well nigh impossible. To appreciate some of our difficulties in the search 

 for tibioita, instead of the varied landscape of an agricultural region with 

 its regular fields and wood lots and its section-line roads, where the 

 collector searches possibl}- in vain for Ophiogomphus, imagine the unbroken 

 and unknown expanse of an almost impenetrable forest with its somber 

 twilight and brooding silence. In such a forest we found tibiata. One 

 would suddenly appear alighting on a bush tw'ig twenty feet awav. A 

 movement would be made towards it and it disappeared as quickly as it 

 had come. The collector resumes his aimless wandering, an hour passes 

 before another one is seen and the experience repeated, or night may come 

 without another one having put in an appearance. The four of us in 

 several days saw less than a dozen specimens. At another season conditions 

 might well be very different. When the rains have started little streams 

 through the forest, and when some of the muddy depressions have become 

 ponds, the capture of tibiata may be a less difficult matter. When we saw 

 them they ranged freely through the forest, flying at varying heights ancl 

 resting on twigs from four or five feet to ten or twelve feet high without 

 any of the effort at concealment which Gynacantha so often shows and 

 which Dr. Calvert has well described (9, p. 315). Sometimes at rest the 

 abdomen was more nearly horizontal than vertical, and at such times the 

 yellow tip])ed abdomen and the position strongly suggested a gomphine 

 rather than an aeshnine. 



Dr. Calvert has described the living male from P'eralta, March 23, 1910. 

 as follows: Eyes bright green above, yellowish green below, posteriorly 

 narrowly edged with blue ; three horizontal rows of pseudopupillae visible 

 in profile view. Frons above blue on each side of the T-spot, green 

 anteriorly, as also are clypeus, lips, basis of mandibles, thorax, abdominal 

 segment t. basal half of 2 and much of 3-5. I'lue as follows: rear of head 

 inferiorly. interalar region of hing wings, auricles, posterior half of 2, 

 and each side of the base of 3, which latter merges graduallv into the 

 green. Dark brown or black as follows: rear of head superiorly, a trans- 

 verse stripe just behind the auricles, and another apical one on 2, a mid- 

 dorsal line, an apical transverse stripe, and a transverse stripe at the 

 median carina on 3-7, and a transverse stripe at five-sixths the length on 



