186 U. S. NATIONAL MUSEUM BULLETIN 216 



Specimens (3d 1 , 279): From Alabama (Thomasville) ; Arkansas 

 (Howard Co.); District of Columbia (Rock Creek Park); Florida 

 (Newman's Lake in Alachua Co.); Georgia (Atlanta); Illinois; Mary- 

 land (Cambridge, Mayo, Ocean City, and Takoma Park) ; Massachu- 

 setts (Cambridge); New Jersey (Moorestown) ; Ohio (Montgomery 

 Co. and Put-in-Bay); Ontario (Point Pelee); Pennsylvania (Paupack); 

 South Carolina (McClellanville) ; Tennessee (Knoxville) ; Texas 

 (Mitchell Lake at San Antonio); and Virginia (Falls Church). 



Collection dates are from mid-spring to mid-fall. Unusually early 

 and late dates of interest are: April 16 at Atlanta, Ga.; April 20 at 

 Thomasville, Ga.; May 4 at Falls Church, Va.; May 13 in Howard 

 Co., Ark.; September 14 and October 27 at Mayo, Md.; September 

 24 and 29 at Falls Church, Va.; October 27 at Takoma Park, Md.; 

 and November 23 at Newman's Lake, Alachua Co., Fla. 



Hubbell (loc. cit.) reports this species in considerable numbers on 

 the webs of spiders on the shore of Newman's Lake, Alachua Co., 

 Fla., walking about on the surface of the webs, or crawling through 

 their meshes. We have studied one of his specimens and report his 

 locality above. Other biological data are on pin labels as follows: 

 d% 9, reared from spider nest, Cambridge, Mass., Apr. 12, 1917, 

 A. M. Wilcox. 9, reared from spider eggs, Wilcox. 29, reared from 

 spider eggs, Put-in-Bay, Ohio, Mary Anten. 9, parasite on spider 

 eggs, Mitchell Lake, San Antonio, Tex., May 15, 1914. Three of 

 the nine times we have collected the species it has been taken in woods 

 at the edges of lakes, where spiders were common because of the 

 abundance of midges and other aquatic insects. 



This species occurs in the Austroriparian and Carolinian faunas. 

 It is adult throughout the growing season. 



III. NOTATOR GROUP 



Areolet present, pointed or narrowly sessile above; carina between 

 metapleurum and metasternum present only anteriorly, usually as a 

 short ridge or tubercle behind middle coxa; propodeum without a 

 distinct dorsolateral longitudinal ridge. 



This is a Neotropic group, with one species (notator) reaching 

 southeastern United States. 



4. Tromatobia notator (Fabricius), new combination 



Figures 322,e; 367 



Pimpa notator Fabricius, 1804, Systema piezatorum, p. 115; 9 . Type: 9 , 



[Probably from Essequibo, British Guiana] (Copenhagen). 

 Clistopyga? lateralis Cresson, 1865, Proc. Ent. Soc. Philadelphia, vol. 4, p. 34; 

 c?, 9- New synonymy. Lectotype: 9 , Cuba (Havana). 



