187 



Figures. 



Orbicula l/evis. PL P. Fig. 10. Shell, attached to stone. PL 26. 

 Fig. 151. Shell, removed from its place of attachment, and turned 

 over to show the slit in the lower valve. 



Genus 5. LINGULA, Bruguiere. 



Animal ; with the cirrhated arms elongated and fleshy, disposed 

 in about six coils ; mantle-lobes distinct and frilled all round, 

 firmly adhering to the shell and united to the epidermis. 



Shell ; nearly equivalve, oblong, compressed, gaping at each end, 

 thin, horny, flexible, mostly blue-green, attenuated and forming 

 a beaked umbo in each valve at the posterior end, where it is 

 affixed to a transparent horny pedicle, from one to six inches in 

 length ; no hinge. 



The Molluscan series of invertebrate animals closes with a Brachiopod 

 of similar organization to the previous genera, having well-developed cir- 

 rhated arms folded in coils, and wide-spread frilled mantle-lobes, but it is of 

 different habit, and forms a very different kind of shell. The Lingula do 

 not live attached to rocks, but are found imbedded in the mud of shallow 

 bays and harbours, or in sand, which it appears to perforate. They affix 

 themselves to foreign substances, but they bear away from their place of 

 attachment by the aid of a variously lengthened flexible pedicle, tubular 

 and horny, like the pedicle of a cirrhipede, and the body, elongated at the 

 end of it, secretes an oblong horny shell, almost as flexible as the pedicle, 

 of the shape of a duck's bill. The mollusk reaches in this way from its 

 place of attachment to the length of six or eight inches and more. 



Though not common, the Lingulm abound in their particular haunts in 

 low-water. Mr. Cuming once saw as many as twenty bushels of L. anatina 

 washed ashore in the Bay of Manila after a stormy typhoon. Another 

 favoured locality appears to be about Moreton Bay, Australia. Three of 

 the species are from the Sandwich Islands, California, and the West 

 Indies. 



Species. 



1. albida, Hinds. 5. exusta, Reeve. 9. ovalis, Reeve. 



2. anatina, Lam. 6. liians, Sicain. 10. semen, Brad. 



3. Antillarum, Reeve. 7. hirundo, Reeve. 11. tumidula, Reeve. 



4. Audebarti, Brod. 8. Mnrphiana, King. 



