NOTES AND EXHIBITS. 189 



is of a felspathic character, of a pale buff colour, and has a 

 laminar structure, but the grinding surface is worn quite smooth 

 and slightly concave by rubbing ; the seed to be ground is laid 

 on the stone and rubbed with a small piece of flat stone of a 

 similar nature to the large one (two samples of these stones 

 accompanied the exhibit). The stone is the property of Mr. Frank 

 Hill, who has placed it in the exhibitor's hands for presentation 

 to the Museum. 



Dr. Cox also exhibited photographs of Turbo Jourdani, Kiener, 

 showing the operculum in situ, and its inner side after removal 

 from the shell, all natural size; and offered the following remarks. 

 " As the specimen from which the operculum was taken contained 

 it attached to the dead animal, there can be no doubt about its 

 genuineness ; it was obtained by my friend Mr. Irvine at Geo- 

 graphe Bay, Western Australia. The shell is about 14 centi- 

 metres long and 12J wide, and has a decidedi j^hasianella aspect 

 in colour and smoothness of surface ; the operculum is 95 milli- 

 metres in its greatest diameter and 80 in the opposite, solid, 

 ponderous, stony, white on the external surface and smooth ; the 

 reverse is flat, slightly excavated, and covered with a chestnut- 

 brown epidermis ; the spire is excentral in the long diameter, 

 25 mm. from the lower edge, and about 4 mm. to the right of the 

 central line with the internal surface towards one. It weighs 

 7f oz. I have known of the existence of these opercula for 

 many years, but have been unable hitherto to ascertain to what 

 species of Turbo they belonged." 



Also, a remarkable deformed example of Cyiwcea vitellus, Linn., 

 from New Caledonia (Plate xv., figs. 3 and 4). 



Mr. Skuse exhibited specimens of the pupa cases and imagines 

 of Batrachomyia nigritarsis and B. quadrilineata, described in 

 his paper. 



Also some grass which had been kept dry for more than twelve 

 months, and still contained the living larvae of Lasioptera 



