28 
Psyche 
[March 
of spiracles, as seen on the first and second abdominal segments 
of known neuroptyngine larvae, can be thought of as a consequence 
of total loss of the dorsal scoli of these segments. Support for this 
view of spiracle placement can be found in the European genus 
Ascalaphus (figure 10) and in several African and Australian forms 
already mentioned, in which intermediate stages in the loss of the 
anteriormost dorsal abdominal scolus can be seen to be correlated 
with dorsad migration of the associated spiracle. However, none 
of these ascalaphine forms carries this tendency to the second ab- 
dominal segment: here, the situation is exactly the opposite of that 
seen in Neuroptynginae, since the ventral rather than dorsal scoli 
suffer reduction (figure 10, Scvg). Note that acceptance of the 
above interpretation of scolus/ spiracle evolution forces us to accept 
the larger (“primary”) scoli on abdominal segments three through 
eight in New World neuroptyngines as derivatives of the ventral 
rather than dorsal series; this view gains additional support from 
the relative shapes of the various scoli in Ascaloptynx (figure 5), 
but compels us to consider the “primary” abdominal scoli of ascala- 
phines and neuroptyngines as non-homologous. 
A final point concerns the chaetotaxy of the various larvae and 
some associated behavior patterns. None of the known neuroptyn- 
gines is a debris carrier: protective coloration is achieved through 
the presence of cuticular or epidermal pigments and clumps of 
colored, often scale-like setae. The one larva of possible neuroptyn- 
gine affinities that has been described in the literature, “Tmesi- 
basis” from Africa, shares with Ascaloptynx and its Central Amer- 
ican relatives similar pigmented setal scales (Withycombe, 1925). 
On the other hand, littering of the dorsum is widespread in the 
Ascalaphinae, having been described in such distantly related 
forms as Ululodes, Ascalaphus (Brauer, 1854; Withycombe, 1925); 
and personal observation), Helicomitus dicax (Ghosh, 1913), and 
several unassociated Australian species. It may be that the absence 
of littering may simply be correlated with arboreal or leaf-associated 
habits: several primarily arboricolous or litter-dwelling ascala- 
phines apparently remain naked (Westwood, 1888; Froggatt, 1902; 
Gravely and Maulik, 1911; Fraser, 1922; and Tillyard, 1926), as 
do a number of unassociated forms resembling bark, lichens and 
green leaves (von Someren, 1925; Withycombe, 1925; Wheeler, 
1930). However, the possibility remains that the ability to place 
and secure items of sand or debris on the body has evolved entirely 
