THE BIOLOGY OF THE HYMENOPTEROUS INSECTS OF THE FAMILY CHALCIDIDiE.-11 V L. (). llinVARD. The. piirasitic llyiiien<)i)tcrii as a wlioU' may be classed amon^ the entozoic parasites, yet their life is ento/oie throii^^h only one stage of the existence of the individnal. In tlic adult sta<;e they are active creatures of an especially hi<;h degree of organization, and t-xhibit no trace of the degradational features characteristic of the epizoic i»ara-sites, nor yet of those entozoic forms whose whole life round is jiara-sitic. Xor are their larv;e especially degraded beyond those of tin-non-]);n'asitii' families of the same order. The phenomena of i)arasitism among tlie Chalcididn do not dillcr in any marked degree from those characteristic of the three other great lamilies of parasitic Ilymenoptera — the Tclineumonidw, Braconida; and Prnvtotrypidd'. In all four we normally have the eggs laid by the female on or beneath the skin of the host-insect, and the parasitic larva, on hatching, lives in the majority of the cases within the body of its host. It ofren hajipens that parasites, even of the same genus, are ex-teiiial feeders when parasitic upon endophytous insects, an»l internal when [>arasitic u[)on outside feeders. iSomi' lew species, however, are external upon external feeders. Resembling, then, the other families in these general habits, the fol-lowing i)ages will indicate of the Clialcididtv our ktu)wledge of their ]>articular modes of life ami their relations to other insects antl to each other — in fact their general economy. + "Sii{: I take plojisnre in rocoiniiu'tKliiiji for i>ultlicati()n in the I'roccM'dinj^s of tbo MnsiMini the accompanying paper by Mr. L. O. Howard, on the " IJiology of tho ClitilridKhr." Tliis paper is ttascd very larjjely on the collections of tlio Miisenni. an the material in this family has been Hi>ociaUy stiuliod and arranged \i\ Mr. Howard. Respectfully yonrs, C. V. KlI.KY, Uonorarij Curator, Hipartmcnl of InaeclM. Prof. G. Hrown Goode, Aniiisdtnt Secreliiri/, in charge of Xalioiiul .\fiinii(m. t In prci)aring this paper I have had the very rich collection of tlio National Mn-senm constantly before me, and with I'rof. Riley's generous permi.stii<»n have freely used his own impnblished notes and those of the Division of Entomology. Procoodiug.s National Museum— Vol. XIV, No. 881.