96 Bulletin 1, Biological Society of Washington, 11)18. 



and Artemisia caudata. An insect having the same history 

 is the Tenebrionid beetle, Blaps similis. 



Hunting Creek, just below Alexandria, has a very inter- 

 esting flora. It is filled Avith aquatic vegetation, among 

 which Potamogeton robbinsi and Utricularia macrorhiza are 

 its exclusive possessions in this vicinity. The peculiar marsh 

 plants are Eleocharis flaccida, Carex gracillima, Plantago 

 cordata (also found opposite Alexandria) and Eupatorium 

 cannabinum; and mud plants, Isoetes riparia and Micranthe- 

 mum micranthemoides. Other interesting species occurring 

 here are Alopecurus geniculate, Pedicular is lanceolata and 

 Galium asprellum. 



The large marsh and abruptly rising hills at Dyke, a little 

 farther down stream, furnish good collecting in various 

 lines. The marsh is a beautiful sight during the flowering 

 season of the abundant introduced Iris pseudacorus. In 

 this marsh only has been collected the fragrant ladies tresses 

 (Ibidium odaratum). Dyke has produced several additions 

 to the list of crane-flies of the region, and has yielded the 

 only specimen so far obtained of the remarkable horsefly, 

 Merycomyia. The large hymenopteron, Pepsis elegans, re- 

 lated to the western tarantula hawks, has been seen only at 

 Dyke and Mount Vernon. These two localities also are the 

 only known breeding stations in our area for the yellow- 

 throated warbler (Dendroica dominica). Practically all 

 specimens of the Prothonotary Warbler {Protonotaria 

 citrea) seen or collected in this vicinity have occurred at 

 Dyke. 



Mount Vernon is strongly and fittingly distinguished as a 

 breeding site of the Bald Eagle— our national bird thus 

 making its home on the estate where lived the father of 

 our country. Ospreys are usually to be seen over the river 

 at Mount Vernon and in winter, the river from this point 

 downstream is frequented by large flocks of various species 

 of wild ducks. Noteworthy plants found at Mount Vernon 

 are Spigelia marilanddca and Inula helenium. Mount Vernon 

 has yielded a number of the pretty little Scarabaeid, 

 Trichius delta, and the only specimens so far obtained of the 



