174 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Ill 



exclusive of urogomphi. Frontoclypeal area truncate posteriorly. 

 Without seta on basal segment of labial palpus. Up to 6 (usually 3 

 or 4) spinelike setae on each episternum of mesothorax and meta- 

 thorax. Abdominal mediotergites with impressions usually reaching to 

 middorsal line on second to sixth segments, and with 5 to 10 unpaired 

 setae in an irregular posterior transverse row. 



Material used in the study of the group. — Reared material was 

 available for rufifrons and brightwelli. W. J. Brown, of Ottawa, 

 identified the reared adults. 



A. rufifrons (Randall) : Ten examples were examined, including 

 the exuviae of three reared specimens. Eight of the total were from 

 Minnesota, one from Delaware, and one from Maryland. Material 

 associated with available reared adults is listed below. 



8; Carter County, Minn.; Apr. 8, 1933; 2 adults emerged May 3, and May 



4> 1933, respectively; R. Glen. (C.N.C.) 

 i; Centerville, Del.; Apr. 12, 1930; adult emerged May 17, 1930; C. A. Thomas. 



(Pa.C.) 



A. brightwelli (Kirby) : Only the larval exuviae of two reared 

 specimens were available for study. 



2; Cornwells, Pa.; April 1927; C. A. Thomas. (Pa.C. and C.N.C.) 



A. pallidipennis Mannerheim: Eight larvae from Walla Walla, 

 Wash., were examined. These were collected and identified by M. C. 

 Lane. (U.S.N.M.) 



ATHOUS MUTILATUS Rosenhauer 

 Figures 12, c; 34, g, h 



This European species was studied from larvae collected in Ger- 

 many and Denmark. Specimens collected from decaying elms were 

 reported reared to maturity. 



Larva of ^. mutilatus are not closely allied to other known Athous 

 larvae and may be distinguished by the following characters : Caudal 

 notch large, only slightly narrowed posteriorly; urogomphi (fig. 34, 

 g, h) with outer prongs much longer than inner prongs; outer prongs 

 corniform, tips sharp; and abdominal mediotergites punctulate, but 

 lacking transverse rugae and coarse pits. 



The larvae examined measured up to 13 mm. in length. Dorsum 

 pale yellow to yellowish brown with head and thorax distinctly darker. 

 Ninth abdominal segment with 3 rounded "teeth" on each lateral 

 margin of dorsum, and distance between caudal notch and pleural 



