362 INTRODUCTION TO CONCHOLOGY. 



covered with a tliin_, liglit-green_, horny epidermis, in some 

 species peculiarly wrinkled or shrivelled and projected over 

 the margin; the hinge is composed of three irregularty- 

 forked teeth in each valve, some of which are bifid, the 

 valves being united by an oblong external ligament. They 

 dwell in brackish water, in the mouths of rivers, at their 

 confluence with the sea, and are found imbedded in the 

 mud. As yet they have only been discovered in the eastern 

 hemisphere ; and among the several new species added by 

 Mr. Reeve, in his ' Conchologia Iconica,^ to the two that 

 were previously known, the localities of eight are as 

 follows : — one inhabits the rivers of China, one the Ganges, 

 three pertain to rivers flowing into the Bay of Manila, and 

 three to such as water the islands of Zebu, Negros, and 

 Luzon, of the Philippines. 



Some of the genus are elegantly varied. The Waxen 

 Glauconome [G. cerea), which inhabits the Ganges, is a 

 dehcate pale straw-coloured shell, resembling wax. The 

 Short Glauconome {G. ciirta), is of a shorter ovate form 

 than any of its brethren ; it is covered with a fine silken 

 epidermis, and is beautifully tinted in the interior with a 

 bluish salmon-colour. A variety of the Wrinkled Glau- 

 conome {G. riigosa), the largest of the genus, presents' a 



