NFAV DRAGON-FLY NYMPHS— NEEDHAM. (V.)8 



border of the median lobe sliohtly concave, with minute double tooth 

 in the middle and with the usual fringe of scales, the lateral lobes short 

 and stout with lono- strong- movable hook and without end hook, l>ut 

 with 7-8 l)ackwardly serrate teeth on the iiuier margin. (liiniiiislijiiM- 

 in size toward the base. 



Legs depressed, hairy on edges, and marked with curved longitudi- 

 nal bare scars, the fore and middle tibia^ armed with strongly developed 

 and conspicuous burrowing hooks. The wing cases reach posteriorlv 

 as far as the fourth abdominal segment. 



Abdomen strongly dei)ressed, lanceolate, widest across the middle 

 and sharply pointed at the apex. Dorsal hooks rudimentary, repre- 

 sented on segments Q-S by low apical elevations and on }> by an even 

 longitudinal middorsal ridge, whose distal end is slightly projecting. 

 Lateral spines on segments 0-9, on 6 very small, on 7 and 8 suc- 

 cessively longer and stronger and a little divergent, on i» almost as 

 long as the tenth segment, sharp-edged and closely appressed. The 

 middle abdominal segments are of about equal length, the eighth is 

 slightly longer, the ninth is a third longer, and the tenth is half as 

 long as the ninth. Appendages as long as the eighth segment, the 

 laterals a tifth shorter than the others. 



STAUROPHLEBIA RETICULATA Burmeister. 

 Plate XXXIX, tigs. 1.2. 



"" Nicaragua, Escondido River, 50 miles from Bluetields, Septeml)i'r 

 3, 1892,'' collected by Dr. Charles W. Richmond. "' Found on pile 

 near water." 



Length, 51 mm. ; abdomen, 85 nun. ; hind fenuir, !» mm. ; antenna. 5: 

 width of head at front across eyes 9, across hind angles 8 nun.: of 

 abdomen, 9 nun. 



Body elongate, little depressed, not hairy. Head widest across the 

 verv prominent eyes; antennae 7-jointed, pale; ratio of length of seg- 

 ments from base outward 1.5:1:1.5:1: 1.1:1.2:1.1. Labruni promi- 

 nent, rounder in front, with granulate upper surface. Face with a 

 submedian pair of low obtuse elevations: mandibles with a conspic- 

 uous, shelf-like lateral prominence that is armed with numerous short 

 curved spines pointing forward. \'ertex with the ocellar tutu-nle, 

 prominent, deeph' bihd, ending above in two erect acute points: sides 

 of head behind the eyes parallel as far as the rounded hind angles, 

 above each of which is a longitudinal row of three or four tubercles; 

 hind margin concave. Labium (Plate XXXIX, tig. 2) very long, the 

 hinge almost reaching the ba.ses of the hind l(>gs; nientum narrow in 

 its basal two-thirds, suddenly widened at distal end. where the mar- 

 gins are upcur\-ed, shai-p. and spiiuilos(>. Median lolte with :i shallow 



