i^6i. CarpknTKR- — The Puparium of the Grouse-Fly. 225 



In addition to the lines of punctures, the lateral and trans- 

 verse sutures (the " deux sutures " of Dufour and the " Bogen- 

 naht " and " Ringanht " of Iyeuckart and Pratt) along which 

 the forepart of the puparium splits open to allow the escape 

 of the imago, can be traced. The former appears as a simple 

 furrow in the integument, while the latter shows as a very 

 narrow band, distinctly lighter in colour than the surfaces 

 that it separates ; this appearance agrees with the microscopic 

 structure of the cuticle and underlying skin as investigated 

 by Pratt in Melophagus. The transverse suture (" Ringnaht ") 

 surrounds the puparium just in front of the fourth set of 

 transverse puncture-lines (figs. 6, 7). The arched lateral 

 suture (" Bogennaht ") runs around the forward edge of the 

 puparium, uniting the two opposite lateral points of the trans- 

 verse suture, and passing close to the dorsal edge of the 

 mouth-area where it undergoes a slight deflection (figs. 3, 6). 



The most striking region of the puparium is the hinder end. 

 For a short distance in front oi, and a rather greater space behind 

 the last transverse line of punctures, the fine lines forming 

 polygons are absent, and the surface of the puparium exhibits 

 only minute irregular wrinkles. Behind this comparatively 

 smooth area comes the elliptical region, surrounding the deep 

 central depression at the extreme tail-end, at the bottom of 

 which are situated the six stigmata. This elliptical region is 

 most regularly and exquisitely ornamented. It is divided 

 into twelve radiating, wedge-shaped areas (figs. 1, 4, 8). Six 

 of these, of which two are bisected by the central dorso-ventral 

 plane of the body,- exhibit a surface broken up into deep 

 elongate polygonal depressions, separated by markedly raised 

 ridges (fig. 5). The alternating six areas (whereof a pair are, 

 of course, cut by the plane of the lateral edges of the puparium) 

 are far less rugose, but are studded with a number of hemi- 

 spherical tubercles. Strange and interesting in structure 

 though the flies of the Pupipara are, no one has probably 

 claimed admiration for them on the ground of their beauty. 

 But the shining black puparium of Ornithomyia, its whole 

 surface, as it were, cunningly wrought into the most delicate 

 of tracery, appeals to the eye of the observer as strikingly 

 beautiful. For the present at least we can but admire, and 

 Wonder what the meaning of all this ornament may be. 



Science and Art Museum, Dublin. 



