8 ODONATA. 



10. Gomphoides species. 



Selts, Monogr. des Gomph , p. 208. 



PL L, fig. 5, a, b, c, d. 



Nympha, male. Length, 36 mm.; breadth, 6 mm. Skin split, show- 

 ing the imago. 



Locality: Sta Cruz, Brazil. Thayer Exp. Mus. Comp. Zool. 



Body long, slender. Head cordate, hairy, nearly as broad as the 

 body. Eyes large, prominent. Ocelli well developed. Antennae rather 

 short, two basal joints globular ; 3d twice as long, strong, dilated ; 4th 

 short, linear. Vertex flat ; in front of anterior ocellus an impression ; 

 behind the eyes on occiput an oval depressed spot. Mask reaching 

 half-way between fore and middle legs. Breadth half the length, en- 

 larged in front, middle much produced in semicircular lobe, with fringe 

 of bristles. Palpi short, arcuated, not denticulated ; movable hooks 

 longer than palpus and sharp. Prothorax oblong, breadth rather 

 greater than length, sides and angles rounded ; two oblique impressions 

 in front and one behind at middle. Wing-cases reaching middle of 4th 

 segment, Legs short, strong, hairy ; hind legs more widely separated 

 at base ; fore and middle legs of equal size ; femora stout and arcuated, 

 enlarged at middle ; tibiae somewhat longer, angular. Tarsi shorter, 

 basal joints very small, 2d longer, knife-shaped, bent outward ; claws 

 very small, strong, rather blunt ; tibiae and tarsi have black spines 

 on outer side. Legs formed for burrowing. Hind legs more slender, 

 reaching 6th segment; femora and tibia? straight; tarsi 3-jointed, 2d 

 shorter than 3d, claws longer, pointed. Abdomen conical, venter less 

 rounded than dorsum, tip extremely tapering. Segments of nearly 

 equal length, gradually decreasing, except 10th, which is longer than 

 7th, 8th, and 9th together, and nearly cylindrical. Side-edges rather 

 prominent. Segments 7, 8, and 9 have lateral spines. Segments 4, 5, 

 and 6 have dorsal spines, strongest on 4 and 5. Anal appendices py- 

 ramidal, short, sharp, all five of equal length. Sexual parts are visible 

 on 2 and 3 ventral segments. 



This nympha belongs perhaps to the genus Gomphoides (sub-genus 

 Aphylla) brevipes Selys, the imago of which has the 10th segment of 

 equal length to 9th, while the others, from Brazil, have 10th segment 

 shorter. A nearer determination is not at present possible. 



