56 Proceedings of the Biological Society of Washington. 



1836. Order Thysanoptera Haliday 



1838. Tribe Physopoda Burmeister 



Thrypnnx Blanchard* 



Malacoptera BruUe* 



1852. Order Physapoda Haliday-Walker 



1855. Order Thripsina Newman 



1855. Group Thripsidse Fitch 



1856. Family Thripididx Fitch 



Small, slender, usually depressed, Orthopteroid insects, generally capa- 

 ble of flight and frequently saltatorial, feeding on plant-saps and excep- 

 tionally on animal juices. Metamorphosis direct ; penultimate instar 

 often quiescent. Wings developed gradually and applied externally. 

 Reproduction always oviparous, often parthenogenetic. 



Head vertical, moderately movable, usually with large compound eyes 

 and three ocelli. Antennae slender, four- to nine-segmented. Mouth 

 parts hypognathous, haustellate, conical, asymmetrical, consisting of a 

 triangular labrum fused with the two pairs of maxillse to form a sheath 

 in which move three piercing bristles. 



Prothorax free, movable. Mesothorax and metathorax united, each 

 with a pair of stigmata. Wings often rudimentary or lacking, four in 

 number, nearly similar, slender, with few or no veins, and closely fringed 

 with very long hairs. Tarsi one- or two-segmented, with one or two claws, 

 between which is a bladder-like organ. 



Abdomen ten-segmented, terminal segment often tubular ; first segment 

 short, more or less united with the thorax. Ovipositor, when present, 

 consisting of two pairs of gonapophyses pertaining to segments 8 and 9. 

 Stigmata present on abdominal segments 1 and 8. 



The writer has followed previous authors in employing the name Thy- 

 sanoptera in preference to the earlier name Thripsites (or Thrypsites), 

 because it is definitive, more satisfactorily formed, and is in general 

 acceptance by entomologists. It has two years priority over Physopoda, 

 which would otherwise, perhaps, be a more satisfactory term than either. 



Key to Subfamilies and Higher Groups. 

 I. — Female with an ovipositor formed of two pairs of gonapophyses aris- 

 ing from segments 8 and 9 of abdomen ; terminal abdominal seg- 

 ment seldom tubular, that of female longitudinally divided beneath 

 and usually conical, that of male usually bluntly rounded, never tubu- 

 lar. Wings microscopically pubescent; fore wing with marginal vein 

 and at least one longitudinal vein attaining tip. 



Suborder Terebrantia Haliday, 1836. 

 (=Su border Thripoidea Karny, 1907.) 

 A. — Ovipositor curved upward. Wings broad and rounded at tip. 

 Body not depressed. Antennae nine-segmented. 



Superfamily ^olothripoidea nov. 

 (=Tribe jEolothripides Bagnall, 1914.) 



* I have been unable to locate the places of publication of these names. 



