STRUCTURE OF PROBOSCIS OF OPHIDERES FULLONICA. 387 
as along the proper cutting edge, it will resemble the bayonet- 
shaped proboscis-tip. 
It will be seen that the teeth on the ventral edge of the 
saw point towards the tip, those forming the two dorsal edges 
pointing in the opposite direction. ‘Therefore, as the saw is 
thrust into the orange, the ventral teeth will begin to cut ; 
as it is withdrawn the dorsal ones will take up the work. If 
a man were to work with a saw, which besides the usual teeth 
possessed others on its back pointing in the reverse direction, 
and if he were, besides sawing in the usual way, to cut another 
piece of wood at each back stroke with the upper edge, he 
would have to press first with the lower edge of his tool 
and then with the upper one. ‘This alternation of pressure is 
effected in the saw of Ophideres in a curious manner. In Fig. 
1 three strong ridges with corresponding depressions may be 
seen running obliquely across the side of the proboscis, each 
being continuous with one of the projecting ventral teeth ; in 
this drawing they are necessarily represented by light and 
shade, but in Fig. 2 they are seen in profile. It is clear that 
the effect of the obliquity of these ridges will be to make the 
ventral teeth “ bite’ as the saw enters the fruit, and that the 
moment it begins to be withdrawn the pressure will be taken 
off the ventral teeth and transferred to the dorsal ones, which 
are thus in their turn forced up against the part of the wound 
on which they have to work. Moreover these ridges, assisted 
by the barbs (4, Figs. 1 and 2), convert each lateral surface of 
the saw into a rasp; the curious peg-like teeth (/¢), of which 
there are three on each lateral surface, aid in the same object. 
Whether the frill of delicate spines (dsp, Fig. 1) on the 
dorsal aspect assist in the rasping or sawing action [ cannot 
determine, nor what the special funetion of the stronger 
spines in the ventral surface (vsp) may be. 
Mr. A. G. Butler has been so good as to inform me that 
Catocala nupta would be a fair representative of the nearest 
British allies of Ophideres. In accordance with its simple 
nectar-sucking functions, the proboscis of Catocala is very 
different in structure to that of Ophideres.! It ends in a 
blunt tip, and has none of the saw-like teeth and ridges 
described in Ophideres; it is covered on its dorsal aspect 
with a number of curved spinous hairs and with blunt 
papillae like those figured by Newport (‘Cyc. of Anat. 
and Phys.,’ vol. 11, p. 900) on the proboscis of Vanessa 
"Mr. Butler says that “the Catocalide differ much in the form of the 
palpi from the Ophideride ;” so that some difference might be expected in 
the structure of the proboscis. 
