THE CANADIAN ENTOMOLOGIST. 377 



number of specimens identical with Needham's form from Go Home 

 Bay, Georgian Bay, Ont. (date and collector unknown) and two 

 exuviae, received from Mr. C. H. Kennedy, form Lake McKinney 

 Tahoe, California. I feel confident that they all belong to hud- 

 sonica, in spite of these differences in the development of the 

 dorsal hooks. There is no other species in the Georgian Bay region 

 which this nymph could fit. Leucorrhinia proximo, is the only 

 species which could be considered, but it is much larger than 

 hudsonica, whereas these nymphs are all of about the same size. 



Explanation of Plate XXV. 



Figs. 1-3. — Mshna tuber culif era; 1, female nymph (x2) ; 2, 

 labium; 3, terminal segments and genitalia of female nymph. 



Fig. 4. — JEshna palmata, right supra-coxal processes. 



Fig. 5. — JEshna umbrosa, right supra-coxal processes. 



Figs. 6-8. — Sympetrum pallipes; 6, lateral view of abdomen; 

 7, dorsal view of terminal segments; 8, portion of distal margin 

 of lateral lobe of labium. 



Figs. 9-12. — Leucorrhinia hudsonica; 9, lateral view of abdo- 

 men of exuvia from Nipigon, Ont.; 10, same, from another Nipi- 

 gon specimen; 11, dorsal view of terminal segments; 12, portion 

 of distal margin of lateral lobe of labium. 



NOMENCLATURAL AND CRITICAL NOTES ON 



HEMIPTERA. 



BY E. P. VAN DUZEE, LA JOLLA, CALJF. 



For the past two years, as many of my correspondents know, 

 I have devoted all my spare moments, which have been all too few, 

 to the preparation of a catalogue of the North American Hemiptera. 

 This is now practically completed, but as it is not certain just 

 when it will be in print, it seems best to call attention in advance 

 to certain features of the nomenclature used, partly in the hope 

 that criticism may show oversights and errors in time for correction 

 in the manuscript. 



The following synonymy calls for special mention : 



Genus Cydnus. — When founding this genus, Fabricius desig- 

 nated tristis ( = aterrimus Forst.) as type. Cydnus must therefore 



November, 1914 



