1976] 
Henry — Larval Owlflies 
5 
Newly hatched larvae of both species were fed single live Dro- 
sophila melanogaster (Meigen) and D. hvdei (Sturtevant) daily 
for the first week. They were later fed twice a week with first and 
second instar nymphs of Blattella germanica (Linn.). Each late 
third (last) instar ascalaphid was fed an adult female B. germanica 
roach once a week. 
Larvae in various stages of development were killed in and ini- 
tially fixed and injected with Bouin’s solution. After 12 to 24 hours, 
specimens were transferred to 70 percent ethanol or, for mild clear- 
ing of sclerotized structures, to Weaver’s dissection and preserva- 
tion fluid: 2 parts 40% formalin, 1 part glacial acetic acid, 8 parts 
chloral hydrate, and 29 parts distilled water. When greater clearing 
was required, warm 10 percent potassium hydroxide or Nesbitt’s 
solution (Nesbitt, 1945) proved adequate. Very small specimens 
and structures were run through dehydrating solutions of alcohol 
and xylene and mounted in Damar on depression slides. Observa- 
tion, dissection and figuring of specimens involved use of a Wild 
M5 stereoscopic dissecting microscope equipped with integral 
camera lucida, and various Bausch and Lomb compound micro- 
scopes fitted with 10 x 10 micrometer eye-piece grids. 
Most of the methods outlined above apply equally well to the 
collection, rearing, preservation and observation of other ascala- 
phid immatures used incidentally in this study, including an un- 
identified species of Ululodes from central Florida and Ascalaphus 
libelluloides (Schaffer) from south-central France. Large numbers 
of viable eggs of the latter European species were found on low 
herbiage clothing rugged hillsides near the Aveyron River outside 
the village of Penne, in the French district of Tarn-et-Garonne. 
External Morphology 
The characteristics that define larvae of the extant Ascalaphidae 
and that set this family apart from other myrmeleontoid taxa like 
Psychopsidae, Nymphidae, Myrmeleontidae, Nemopteridae and 
Stilbopterygidae* have been discussed at length in the works of 
Withycombe (1925) and MacLeod (1964, 1970). These include 
(a) posterior margin of the head capsule strongly cordate, (b) pres- 
* Larvae of this peculiar Australian and South American family are not suffi- 
ciently known to permit confident comparisons; immatures of Psychopsidae, 
Nymphidae and Nemopteridae are also poorly known. 
