190 ORDER HYMENOPTERA. 



The first section has two subsections, the second containing two divisions : 



Subsection I. PHVTiPHAaA : Abdomen sessile : larrte feeding upon vegetable matter. This containB 



the fiuuiliea Tenthredimda and Urocerida, 

 Subsection II. Entomophaoa : Abdomen attached by a portion of its transverse diameter : larvre 

 with slightly developed trophi, and for the most part feed para.sitically upon other living insects. 

 Division 1. Spiculifera : Abdomen with an elongated plurivalve oviduct : larvas for the 

 most part feeding upon other living insects. This division contains, as at present constituted, 

 the Cynipida, Etaniidm, Idineumomdce, Chalcidida and Proctotrupidee. 

 Division 2. Tubulifeea : Extremity of the abdomen tubular, retractile, and furnished with 

 a minute sting : larvae feeding upon the larvas of other hynienopterous insects, or upon 

 dead insects deposited by the parent with her eggs for the support of the young when 

 hatched. The Chrysidida. 



The second section has two subsections : 



Subsection I. Pe.«dones { Latreille) : The basal joint of the tarsi cylindrical : larvae feeding upon 

 stored insects, or animal fluids provided by neuters. Families Crabronida, Larrida, Bembecida, 

 Sphegida, Scoliida, MutillidcB, Formicidce, Vespidce. 



Subsection II. Mellifera ( Latreille) : Basal joint of the posterior tarsi dilated for pollen-bearers : 

 larvae feed upon honey or pollen-paste deposited by the neuters. Families AndreiiidtB, Apida. 



Tenthredinidae. 



This family comprehends those hj-menoptera usually called sawflies. The antennse are more 

 variable as to the number of joints, than in most of the insects of other families. The 

 families of the order are formed from considerations that relate to the number and form 

 of the joints of the antennse, and the number and form of the cells of the wings. 



The insects of this family are less active than the wasps or ichneumon-flies : they fly 

 sluggishly, and do not appear anxious to escape when about to be captured. The wings 

 fold horizontally upon the body when at rest. The female is provided with an instrument 

 resembling a saw, or rather a double saw, which is lodged in a fissure beneath the abdo- 

 men, and covered by two narrow pieces that perform the office of a scabbard. The two 

 blades of the saw are placed side by side, and so skilfully articulated that when withdrawn 

 from the scabbard they move up and down. This saw, however, has different forms in 

 different sawflies : it has, moreover, one advantage over the carpenter's saw, which only 

 cuts in one direction, and therefore is liable to pinch if it is not well set, especially when 

 employed in sawing green wood ; but the saw of the fly has teeth upon the sides, so that 

 it can move easily by cutting a free groove. It might perhaps be called a rasp or file, as its 

 teeth have the form of the teeth of these instruments. "When in use, the saw moves in a 



