2.1 



THYSANOPTERA AND ORTHOPTERA. 205 



lack of arrangement need not be a serious defect, inasmuch as the 

 taxonomic order is preserved in the "List of Species" which follows, 

 and the purpose of the key is only the identification of species. 



Key to the Species of Thysanoptera taken in Huron County, Michigan. 



a. Terminal segment of abdomen conical or bluntly rounded, not 

 a tube. Female with curved, saw-like ovipositor. Suborder 

 1. ■{ Terehrontia. 



I b. Terminal segment of abdomen a slender, slightly tapering 

 [ tube. Female without ovipositor. Suborder Tuhulijera. 



Suborder Terehrantia. 



■ a. Ovipositor of female curved with concave side up. Fore-wings 

 with distinct cross veins. Antennae nine-segmented. Fam- 

 ily Aeolothripidae. 

 Ovipositor of female curved with concave side down. Fore- 

 wings without distinct cross veins. Antennae six-to nine- 

 segmented (nine only in genus Heterothrips). Family 

 Thripidae. 



Family Aeolothripidae. 



( Single species found. Wings with three white bars, at base, 

 \ middle, and tips respectively. Aeolothrips jasciatus, p. 207. 



Family Thripidae.. 



a. Antennae nine-segmented. Heterothrips salicis, p. 208. 



b. Antennae eight-segmented (sixth segment may be apparently 

 divided by an obliciue groove). (5). 



c. Antennae seven-segmented. (11). 

 j d. Antennae six-segmented. Aptinothrips rvfus var. connoticornis, 

 [ p. 211. 



f a. Second segment of antenna elongated on its outer side to form 



I a conspicuous, more or less angular process. Chirothrips moni- 



I catus. p. 208. 



[ b. Second segment of antenna symmetrical. (6). 



a. Prothorax without any prominent spines. (7). 



b. Prothorax bearing few or many conspicuous spines (8). 

 a. Always wingless. Eyes small, composed of but few facets. 



Ocelli wanting. Sixth segment of antennae apparently not 



7. \ divided by an oblique grove. Aptinothrips rufus, p. 210. 



I b. Usually winged. Eyes of normal size. Ocelli present. Sixth 



[ segment of antenna apparently divided by an oblique groove. 



4. <! 



