18010 



1S5 



8fs.W 



Fig. 4, 



more convenient example can be found iliini in tlievery common Coleo- 

 phora ccEspitifiella. 



Coleophora ccBspitiliella. — Appearing at a time wlu'ii the flowor-heads of its 

 food-plant, Juncus conglomeratus, are fully formed, 

 yet not in actual blossom, the parent moth insinuates 

 her thin, pointed ovipositor witliin the pcriantli of a 

 floret, and affixes an egg to the inner surface of a 

 segment. An examination of the floret usually shows 

 that she lays two eggs before withdrawing her instru- 

 ment, but places them on separate though adjoining 

 segments in the same row ; it depending upon the 

 state of the flower at the time whether that be the 

 inner or the outer row. 



The sheath (8 (sh.) ) is a complete tube, much 

 flattened vertically, the better to match the thin and 

 flat ovipositor, and has the rods, which are about half 

 ns long again as the sheath, inserted into the sides. 

 A good idea of the relative length of the parts can 

 be gained by stating, that when the sheath is fully 

 protruded, the rods extend back into the abdomen as 

 far as the inner margin of the 7th segment, this segment being a very large one, 

 and equalling in length the 6th and 5th together. The sheath is strong, and of a 

 rich amber colour below ; but weak and watery-white above, where, to increase its 

 strength, an amber coloured ridge or back-bone runs down the middle. Its mouth 

 is provided with a straight margin on the upper-side, and on the lower is hollowed 

 out in the centre into a large notch, from which there rises on either hand a broad, 

 ear-like projection, with an indented outline, and dotted with long tactile hairs, that 

 reaches round the side to the dorsal aspect. Instead of the usual cylindrical shape, 

 the ovipositor is flattened into a very thin, blade-like instrument, in which the plates 

 (ov. pi.) form a strong, amber-coloured, and rather narrow margin all round, whilst 

 the centre is occupied by the soft visceral tube (v. t.). The mouth is a long slit, 

 extending back from tlie tip for some distance, and opens laterally. In addition to 

 the tactile hairs on the " ears " of the sheath, shorter ones are to be found on the 

 margins of the plates of the ovipositor, especially towards their points. I have 

 come across no insects so favourable as these " probing " ones for exhibiting the 

 genital aperture. In caespititiella it is a low, flat archway on the under-side of the 

 sheath, at its inner extremity (g. a.). The ai'ch, which is moderately deep, is a 

 strong, chitinous structure, capable of resisting much pressure, and is firmly united 

 to the sheath, whilst from its lower corners two distinct and converging elevations 

 are continued down nearly as far as the notch, leaving only a very narrow channel 

 between them for some little distance before their termination. The meaning of 

 these elevations is not quite clear. They may be merely supports of the arch, on 

 the other hand they may be of some special use in the pairing of the sexes. 



Fig. 4.— Ventral view of last three segments of C. caspilitiella. ov. pi., Plate of ovipositor. 

 V. t., Visceral tiibe. g. a., Genital aperture. 



{To be continued.) 



