No. 22.] HYMENOPTERA OF CONNECTICUT. 19 



PARTS OF THE HYMENOPTERA EMPLOYED IN THE 

 DESCRIPTION OF THE MEMBERS OF THIS 



ORDER. 



Original diagrammatic drawings of representative species of 

 the Hymenoptera, with the more important parts used in the 

 classification of this order named thereon, are made use of in 

 this work for the purpose of graphically presenting to the reader 

 what it is believed could be but insufficiently expressed in the best 

 word pictures of the same. 



Of these drawings it needs to be said that the one of Ptero- 

 nidea ribesi (Fig. i), as well as those of the head and abdominal 

 sockets of Exochilum morio (Fig. 2), will be of use in the work- 

 ing out of the meaning of the descriptions of any of the Hymenop- 

 tera, but especially with reference to the Tenthredinoidea ; and 

 that the drawing of Chlorion (Ammobia) ichneumoneum (Fig. 

 14) also serves a double purpose in that it graphically shows what 

 parts are meant by many of the terms used in the elucidation of 

 the differences between species, etc., in the Hymenoptera, but 

 especially with reference to the Formicidae or Formicoidea, 

 Vespoidea, Sphecoidea, and Apoidea. 



Parts peculiar to the other superfamilies, namely, the Ichneu- 

 monoidea, Chalcidoidea, and Serphoidea or Proctotrypoidea, 

 are illustrated respectively by the drawings of the following: 

 Ichneumon centrator, Diastrophus nebulosus, Phasgonophora 

 sulcata, and (Proctotrypes) Serphus caudatus. 



The names of the parts in the different drawings have been 

 arranged so that the parts themselves might not be obscured by 

 the appellations ; thus, the names of the veins are given in con- 

 nection with the wings of the right side of the body, and the 

 names of the cells with the wings of the left side of the body, etc. 



According to the latest nomenclature, the veins and cells of the 

 wings have names different from those formerly used ; hence 

 the names of the old system, which are printed in the dia- 

 grams, together with their equivalents in the new or Comstock- 

 Needham system, are given for comparison in parallel columns.* 



*For the statement of the Comstock-Needham nomenclature, in the Tenthredinoidea, 

 the writer is indebted to Professor A. D. MacGillivray ; in the other superfamilies, to Dr. J. 

 Chester Bradley, 



