May, 1918] Parasites of Leaf-Hoppers 265 



H. americanus Perkins. 



Gonaiopus bicolor Ashmead, Swezey, The Ohio Naturalist, v. Ill, p. 447-8 



(9), 1903. 

 Labeo lon^itdrsiis Ashmead, Swezey, The Ohio Naturalist, v. Ill, p. 447-8 



(c^), 1903. 

 Haplogonatopus americanus Perkins, Rep. Exp. Sta. Hawaii, Ent. v. I, )). 40 



(9), 1905. 



Female: Fcnaiginous to testaceous in color, abdomen black to 

 brownish. Antenna black, apical joint and two or three basal ones 

 pale. Head nearly smooth, pronotum minutely punctured, propodeum 

 dull with fine rugulosity. Length, 2.5 mm. 



Male: Black, mandibles white, teeth brown, maxillary palpi white. 

 Scutellum smooth and shining, metathorax posteriorly rounded, smooth 

 and shining at top, but with lateral diagonal impressions separating 

 punctate areas. Length, 2 mm. 



Columbus, Sandusky, Ohio. Bred from Liburnia campestris 

 and L. lutidenta nymphs and adults. 



Genus Gonatopus Ljungh. 



Gonatopus, Ljungh, Beitr. Naturk, v. 2, p. 161, 1810, Kieffer, Andre Spec. Hym. 



Eur., V. 9, p. 487 nota., 1906, Perkins, Rep. Exp. vSta. Hawaii, Ent. Bull. 11, 



p. 13, (non Perkins, 1905), 1912. 

 Dryninus, Dalman, Analecter ent., p. 14, 1823. 

 Neogonatopus Perkins, Rep. Exp. Sta. Hawaii, Ent. v. 1, p. 42, 1905. 



Female: Head dorsally more or less slightly concave, maxillary 

 palpus four-jointed, labial palpus two-jointed. Mesonotum and scu- 

 tellum not visible. Fore tarsal joint, one and four long, the three others 

 short; median chela arm distally bent inwards, ventrally with rows 

 of lamellaj; lateral chela arm without lamellae or teeth, at the most 

 with a tooth before the distal end, often ventrally with rows of spines. 



Male: Differs from Haplogonatopus chiefly in configuration of the 

 head as follows: Concavity on the frons much smaller and vertex less 

 angulate. There may be exceptions to this, however, as for instance, the 

 male of Gonatopus erythrodes (Perk.). The maxillary palpus is four- 

 jointed in comparison to that of Haplogonatopus which is two-jointed. 



Key to Species. 



1. The entire thorax smooth and shining 2 



Thorax at least in part dull and transversely rugulose or punctate 3 



2. Hind thoracic node distinctly hairy, head brown 16. brimnescens 



Hind thoracic node microscopically finely hairy, head yellow.. 17. pallidiceps 

 Thorax not hairy 7. decepiens . . . . 



3. The whole thorax finely and thickly transversely rugulose 4 



Thorax at the most only in the smallest part transversely rugulose 5 



4. Thoracic spiracles situated on distinct elevations 8. conlorlulus 



Thoracic spiracles not situated on elevations 9. punctalus 



5. Hind thoracic node with distinct erect hairs 6 



Hind thoracic node without hairs 12 



6. Thorax entirely ferruginous 7 



At least the hind node of the thorax dark 8 



7. Lateral chela arm with a tooth before the distal end 11. mimiis 



Lateral chela arm without tooth before distal end 15. mimoides 



