l86 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Ill 



Material used in study. — Examination was made of 12 examples, 

 including the exuviae of 4 reared specimens. The reared adults were 

 identified by W. J. Brown, of Ottawa. 



3; Rhein, Saskatchewan; June 11, 1930; 2 adults emerged July 21 and Aug. 6, 



1930; E. Mengering. (C.N.C.) 

 9; Spencerville, Grenville County, Ontario; June 23, 1938; 2 adults emerged 



Aug. 26 and Sept. 2, 1938; G. H. Hammond. (C.N.C.) 



Genus HYPNOIDUS Stephens 

 Figures 9, /; 10, b; 39 



The name Hypnoidus is used here in the restricted sense and does 

 not include the species which are commonly referred to the genus 

 Cryptohypmis. 



Knowledge of this genus is based upon an examination of larvae 

 of dubius (Horn), musculus (Eschscholtz), and the European mari- 

 timus Curtis. These species are very similar and it might be that they 

 represent only one group within the genus. All are believed to be soil 

 inhabiting and dubius is recorded by King (1928, p. 705) as being of 

 economic importance in Saskatchewan. Kincaid (1900, pp. 374-375) 

 described the larva of musculus from Alaska. 



The known Hypnoidus larvae rarely exceed 11 mm. in length, are 

 very pale yellow in color and are readily identified by the absence of 

 spinelike setae on the coxae (fig. 39, ^), by the mandibles (fig. 39, 

 c, g) and by the pointed, undivided urogomphi (fig. 39, /, h, i) . Some- 

 times, especially in musculus, a slight tubercle is present on the latero- 

 posterior aspect of each urogomphus, which might be interpreted as an 

 extremely small outer prong. 



The caudal notch {en) is large, usually transversely ovate and 

 more or less narrowed posteriorly. The ninth abdominal segment lacks 

 the transverse impression, the median sulcus, and the "teeth" on 

 lateral margins, but bears 4 setae on central dorsal area. Nasale {n, 

 fig. 39, a) consists of 3 short, subequal teeth, lateral denticles some- 

 what serrate in niaritimus. Frontoclypeal area pointed posteriorly. 

 Eyes lacking. Gula (fig. 39, b) very long and narrow. One "sensory" 

 appendix on second segment of antenna. Galea reduced to a single 

 segment. Mandible (fig. 39, c, g) with small retinaculum {ret), and 

 finely serrate posterior to base of retinaculum. No distinct impressions 

 on mediotergites of mesothorax and metathorax. Without spinelike 

 setae on thoracic episterna. Abdominal mediotergites slightly rugose, 



