16 BULLETIN 45, UNITED STATES NATIONAL MUSEUM. 



point iMHiig- suiTouuded by stift' hairs; oiitwaidly tUe surface is convex 

 and smooth, except at about two-thirds its length, where there is a tutt 

 of h)iig liairs. At B the same parts are shown as viewed from beneath, 

 together with other parts not visible from above; us, the upper sheath; 

 Is, tlie lower sheath; p, penis; jw, penal claspers, the outer margin of 

 which are fringed with several lon<? spines or hooks; hi, swollen basal 

 lobes, to which the upper and h)wer sheaths are attached. All these 

 organs, except the tips of the upper and lower sheaths, when not in 

 use, are withdrawn within the apical abdominal segments and are only 

 visible when exsertcd. The swollen basal lobes (/>/) and tlie penal 

 claspers (pe) seem not to have been noticed before, and I believe are 

 now pointed out for the tirst time. 



Fig. 11 represents the male genitalia of Proetotrypes coudatus Say, 

 as seen from the side after the removal of the left ventral spine: vs, 

 right ventral spine; ns, upper sheath, slender and davate; Is, lower 

 sheath, very broad and Hat and terminating in four chitinous lobes. 



Pig. 12 represents the same organs in the male of Scleroderma ct/lin- 

 dried, after Westwood: us, upper sheaths, ''the extremities of which 

 are thin and incurved"; Is, lower sheaths, ''broad and each with a 

 broad, simple stipes {(Id), and f<mr terminal l(>bes (<), two of which are 

 setose at the tips, and (me at least more rigid than the other parts." 



In Fig, 13, PI. I, I represent the ovipositor of IScleroderma ephippium, 

 after Westwood. In his explanation he says: 



The parts of the ovii>ositor itself are vevtit'ally compressed, the recurved bases of 

 the spicuhe (e), with their muscular angulated lobe or catch iff), beini^ represented 

 as flattened. By strong protrusion of the spicuhn beyond the extremity of terebra, 

 the curved basal portions of the former arc straightened and brought forward to 

 the base of the t(>rebra, where their dilated angular form prevents tlicm from further 

 protrusion. The parts marked c. e. are the mcmliranous plates connecting the base 

 of the spicula; and of the terebra itself with the interior of the abdomen. 



HABITS OF THE PERFECT INSECTS. 



The imagos are most frequently found wherever their hosts are most 

 plentiful and th<»ir lives are of short duration, seldom extending beyond 

 a few days. Those I have kept in conrtnement live but four or live 

 days, although in freedom they probably live longer. 



The favorite resorts for diapriids, bethylids, and proctotrypids are 

 low, moist places, where there is a luxuriant growth of vegetation and 

 a black or mucky soil, the decaying vegetation attording excellent food 

 for their hosts — dipterous and other larva'. The opening buds and 

 newly formed leaves of plants and trees, and especially along the out- 

 skirts of a dense forest or wood, are particularly attractive to platygas- 

 terids and telenomids, while the bethylids, dryinids, and scelionids, as 

 a rule, frequent the more ©pen fields. In Florida, dry sandy knolls, 

 where the scrub oak grows, are the favorite resort of the bethylids. 

 Species in the genera Epyris and Mesitius, I have taken most frequently 



