AMERICAN HYMENOPTERA. 273 



Descriptions of species beloii$>;iiig t« the genus NYSSON 

 iniiahiting IVortii America. 



BY E. T. CRESSON. 



Our species may be divided into three subgenera, as follows : 



Wings with three submarginal cells. 



Posterior tibiae serrate ; lateral margin of seutellums strongly reflexed, post- 

 scutelluin bilobed ; apex of % abdomen generally' with fiUir teeth. 



PARANYSSON. 



Posterior tibise not serrate; lateral margin of seutellums not reflexed, post- 



scutellum narrow, not bilobed; apex of % abdomen with not more than 



two teeth NYSSON. 



Wings with -two submarginal cells HYPONYSSON. 



PARANYSSOM Guer. 

 Legs ferruginous. 



Apex of % abdomen armed with two teeth arinatus Cress. 



Apex of % abdomen armed with four teeth te.itanns Cress. 



Legs black; apex of % abdomen armed with four teeth. 



Abdomen subsericeous with pale ochraceous pile I'liscipes n. sp. 



Abdomen sericeous with dense bright golden-yellow pile... nn'.^icaiiiis n. sp. 



Paranyssoii arinatns Cress.. (JSfi/sson), Proc. Ent. Soc. Phila. iv, p. 14.i. — 

 9.— Black, opaque, clothed with a very short, more or less dense golden-yellow 

 pubescence, silvery on face and elypeus; mesothorax deeply and coarsely punc- 

 tured, lateral angles of prothorax prominent and subacute; posterior margin of 

 prothorax, the central impressed line of mesothorax, its lateral and posterior 

 margins, the tubercles, mesopleura and sides of metathorax above densely clothed 

 with golden pubescence; scutellum rugose, golden at base; mesopleura with a 

 short subacute tooth beneath tegulse; metathorax coarsely rugose, the long, stout, 

 acute, strongly divergent lateral spine broadly tipped with yellowish, the basal 

 middle irregularly channelled down the middle; tegulae and legs ferruginous, 

 thinly clothed with golden pubescence, coxfe black at base, silvery; wings sub- 

 hyaline, darker in marginal cell and on apical margin, in the posterior ])air 

 the anal and diseoidal cells are separated by a prolonged longitudinal nervure; 

 abdomen rather closely punctured, coarser at base and becoming finer and in- 

 distinct towards the apex, the extreme base silvery sericeous and the apical margin 

 of the segments above bright golden ; on each side of the three basal segments 

 above a rather large, transverse pale yellowish spot, larger and ovate on basal 

 segment and smaller on the third; venter deeply punctured, shining and some- 

 what silvery. Length ..'')0 inch. 



'J,.— Very much like the 9: th^ fourth segment of abdomen above has a 

 small obscure pale spot on each side behind, and the apical segment is carinate 

 on the sides and armed at tip with two small, distant, obtuse flattened teeth. 

 Length .?>a inch. 



Hah. — Cuba. Two specimens. 



Paranysson tciianns Cress., (TVys.s-on), Trans. Am. Ent. Soc. iv. p. 22.3. — 

 9 • — Black, opaque, clothed with a more or less dense, very short golden-ochraceous 

 pubescence, silvery on thorax beneath and coxae; head closely and deeply punc- 



TRANS. AM. I:NT. SOC. IX. (04) MARCH, 1882. 



