300 Sir S. Saunders' Notes on the 



nheaths, which have been here apparently confounded 

 with the '^ hiqmpj/giuin de Sichel," as the supposed 

 " arceau ventraV where all search for sjyirades had 

 proved unavailing ; the spiraculiferous apex of the true 

 luipopfigimn (Sichel) being thus ascribed to the epipygium, 

 or supposed " arceau dorsaV of a non-existent " ?e seg- 

 ment,' ' and the true epipi/gium (Sichel) being regarded as 

 the "segment dorsal qui le precede.'' 



Walker, in ' his 'Notes on Chalcidi^,' says that 

 " Plidsganophora and Halticella agree in general struc- 

 ture " (p. 40) ; and this is more especially witnessed in 

 Dr. Sichel's subgenus Alloeera (Ann. 1865, p. 379), 

 founded on a single example from Algiers {A. bieolor, 

 Sichel, ? ; = Eueludcis Miegii, Lufour, Ann. 1881, pi. 1, 

 fig. 4), which exhibits all the generic characteristics of 

 H. osmicida, though specifically distinct. Thus, in the 

 latter, the dorsal segments of the abdomen are laterally 

 prolonged into a series of overhanging flaps, which con- 

 ceal the ventral region to a considerable extent. Speaking 

 of these in Alloeera, Dr. Sichel says, " Les arceaux ven- 

 traux sont si courts et converts dans une si grande 

 etendue par les arceaux dorsaux, qu'on les voit a peine" 

 (p. 380). The contracted basal portion of this ventral 

 region is depressed far below the rest in the guise of a 

 carinated recess, open posteriorly, and not extending 

 beyond the third dorsal segment ; its sloping sides, of 

 translucent flexible consistency, indicating, in the same 

 species, four or live overlapping segmental divisions 

 firmly welded together, the terminal segment of these 

 being considerably longer than the others. In Chalcis 

 pyramidea, Fab., Jive of these segments are shown 

 (Westwood, loc. cit.) ; whereas in C. Galliea, Sichel, 

 the whole of the ventral segments are described by Dr. 

 Sichel as "fere in carinam comjyressa, rii/a, tenuia, semi- 

 pellucida, subconnata, ita ut idtima unicum tantum 

 segmentum, ah liypopygio valde distans et vaginam amplam 

 ejfingens, constitnant" (loc. cit., p. 373). By the angular 

 gap at the termination of the aforesaid carinated recess, 

 free action is afforded to the terebra from within ; this 

 aperture being apparently' closed at will by bringing the 

 hy])opygium more or less into contact with the salient 

 angle below, as witnessed in some specimens, and 

 doubtless also by the closer conjunction of the projecting 

 dorsal flaps, described by Dr. Sichel (in his Alloeera 

 = Halticella) as "omnium lateribus in ventrem decur- 



