THE CANADIAN ENTOMOLOGIST. 61 



ON RHAGOVELIA OBESA, UHLER. 



BY J. R. DE LA TORRE BUENO, NEW YORK. 



Rhagovelia, Mayr,* is well characterized by the long spindle-shaped 

 deeply-cleft intermediate tarsi, a peculiarity noted by most of the authors 

 who have referred to the genus. This genus is found in Asia, Africa and 

 the three Americas, but the larger part of the known species is native to 

 the Western Hemisphere, no less than fifteen (including undescribed forms 

 in my collection) being Central American. All the species are fluviatile, 

 save two, which are marine. The marine forms are found in estuaries or 

 along the coasts, and by some authors are held to form a different genus, 

 known as Trochopus. 



The one species to be found commonly in the Eastern United States 

 is Uhler's Rhagovelia obesa,\ which can be found in almost any swift 

 streamlet in little congregations, weaving zigzags where the current is 

 most rapid, swimming against it, or else sheltered in the eddy behind 

 some projecting rock, where, in the latitude of New York, tjie rare winged 

 form is most likely to be found. My collection contains specimens from 

 the following regions : New York, Nev/ Jersey, Washington, D. C, and 

 North Carolina. The various local lists we have mention it as occurring 

 in Tennessee, North and South Carolina, Maryland, Virginia, Pennsyl- 

 vania, Massachusetts, Ohio, New Jersey, and Ontario, Canada. Prof 

 Uhler states that it is found in the Atlantic States. 



In their generic characterization, Mayr, Stal (under the generic name 

 Baecula):;: and Uhler note the deeply-cleft intermediate tarsi, but it fell to 

 Champion§ to refer to the tuft of hairs in the cleft in the following terms 

 (which Distant quotes in "Fauna of British India, Rhynchota, Vol. IL, 

 p. 171"): "Rhagovelia is well characterized by the 3-jointed tarsi, and 

 the long, deeply-fissured terminal joint of the intermediate tarsi. la this 

 fissure there is a series of long ciliated hairs arising from a common stem, 

 which are probably extended fan-like when the insect moves about on the 

 surface of the water ; these hairs are sometimes partly extended in dried 

 specimens, but they are usually hidden within the fissure." 



Champion's remarks on the hairs are substantially correct, as can be 



*Verh. Zool., bot. Ges. Wien., XV., 445, 1865. Reise der Novara, Hem., 181. 



11871. Proc. Bost. Soc. N. H., XIV., 107. 



1^1865. Hemiptera Africana, Vol. III., p. 167. 



§1901. Biologia Centrali Americana, H.eteroptera» Vol. II., p. 131- 



February, 1907. 



