412 BULLETIN 45, VNITKD STATES NATIONAL MUSEUM. 



AiiteiiiuK in S l-4-joiiit<'<l, I lie scaiK> iihiioniially ciiliii'^cd, dilated, 

 vrith :i dt^ep eiiiurKiiiatioit within; the tliif^clhun sli<;litl,v incrassatiMl 

 toward ii|M*x, the joints after the first nionilitorni; in 9 12 Jointed, 

 chivate, the scape, linear, the pediee! longer than tlui first flajjellar Joint, 

 joints 'J to ."» sul»e(|nal, sul)};iobnlar, tiic followin{j f'ornunjjf tiie cluh. 



Mandibles bidentate. 



Tlutrax oblonji-ipiadrat*', the protlnnax not visible from above; 

 njesiMiotJim convex, without furrows; nietathorax very short, not 

 eniarjiinated, the angles not acute, in <^ si>ars«'ly, in 9 densely woolly. 



Winjis wanting; in both sexes. 



Abdomen oval, trtmcafe behind, the i)etiole very short, stout, woolly, 

 the sei'ond segment occupying nearly the wlM)]e surface. 



Legs short, stout, comi)ressed, clavate, the tarsi short. 



This curious genus, known only in a single species, has not yet been 

 reeogni/ed in Ameriea, the species described as such by Abbe Provan- 

 cher under the nante J'lati/mhschus iorquuius (Add. a la Faune Hym., 

 p. 18li), being a I)iai)riid belonging to the genus TrophUtpria and allied 

 to J>i<(pria conUa Latr. and J>. carindtu Thomson. 



The genus PUtttfntixrhus was originally characterized from the male; 

 and to the liev. T. A. Marshall we are indebted for perfecting the 

 generic diagnosis by the dis<'overy of the female. Mr. Marshall 

 believes the genus is parasitic on Diptennis hnvte inhabiting low 

 marshes. 



LOXOTROPA Forster. 



llyin. Stiul., II, p. 1£2, 1856. 



(Typo /.. (iculutha First.) 



Hefid subglobose, often oblong, with a frontal sulcus, the occiput 

 rounded; cheeks woolly; eyes rounded; ocelli 3, minute. Antennse 

 in 9 12-jointed, clavate; the three or four terminal joints most fre- 

 quently abruptly, enormously enlarged; pedicel usually much larger 

 than the first funiclar Joint; in $ 14-Jointed, filiform; scape subcla- 

 vate; pedicel short; first and second funiclar joints lengthened, the 

 first slightly the longer, the second thicker and usually curved, the 

 joints beyond oval or cup shaped, seldom nuich longer than Avide. 



Mandibles short, bifid. 



Maxillary palpi, 5-jointed. 



Thorax ovoid; prothorax slightly visible from above, usually covered 

 with a whitish wool, always present at sides; mesonotum smooth with- 

 out furrows; scutellum subconvex, or flat, smooth, truncate at apex, 

 with distinct grooved lines along the sides, and a fovea at base; meta- 

 thorax short, emarginated. 



Front wings pubescent, the submarginal vein terminating in a small 

 stigmated marginal vein before attaining half the length of the wing; 

 basal vein always present. 



