LIBELLULA. 151 



Hob. Lake Michigan, Wisconsin. It migrates in immense flocks 

 (Dr. Hoy); Canada; Massachusetts (Scudder) ; Europe; Asia; 

 Siberia; Kamtschatka. 



Common everywhere that it occurs. The male L. ternaria Say, 

 from Massachusetts, certainly belongs to this species. The female 

 of that species belongs to the following. 



2. L. semifasciata! 



Libellula semifasciata Burm.l Handb. II, 862, 80. Lib. maculata Ramb.! 

 Neuropt. 55, 31. Libellula ternaria Say (9), Journ. Acad. Philad. 

 VIII, 21, 7. 



Reddish-yellow, villose ; front lurid, above terminated with 

 black ; sides of the thorax obliquely twice marked with yellow ; feet 

 black, femora yellowish rufous ; apex of the abdomen attenuated, 

 the dorsum with apical, triangular, fuscous spots, and lateral 

 brighter yellow ones ; superior appendages of the male short, 

 blackish fuscous; base of the wings yellowish, a basal, longitudinal 

 stripe, which is sometimes double upon the posteriors, an abrupt 

 band upon the middle and a pterostigmatical band, sometimes 

 also the apex fuscous; pterostigma large, rufo-fuscous; membra- 

 nule white; fourteen antecubitals; ten postcubitals ; four, or some- 

 times three discoidal areolets. 



Length 37 45 millim. Alar expanse 66 77 millim. Ptero- 

 stigma 5 millim. . 



Hob. New Jersey, Massachusetts, Maryland (Uhler); New 

 York, Savannah, Georgia; Carolina, Florida (Osten Sacken). 



3. L. nodisticta! 



Libellula nodisticta Hagen ! 



Fulvous, clothed with white hair ; front pale, brassy-fuscous 

 above, terminated with black; dorsum of the thorax incanous, each 

 side fuscous, sides pale with four sulphur spots ; feet black, base 

 of the femora fuscous; apex of the abdomen attenuated, fulvous, 

 with a broad dorsal, black stripe ; appendages short, black ; wings 

 hyaline, a basal fascia and a nodal point, black ; pterostigma nar- 

 row, black ; membranule white. Male. 



Thirteen antecubitals; nine postcubitals; four discoidal areolets. 



Length 47 millim. Alar expanse 77 millim. Pterostigma 4 

 millim. 



Hob. Mexico (Saussure). It is allied to Lib. quadrimaculata. 



