CHAMA. 403 



crenulated tooth, inserted in a fossa between the two teeth 

 of the opposite valve ; ligament external, depressed. Mus- 

 cular impressions lateral, wide apart. 



Syn. Globus, Klein. Stola, Browne. Jataronus, Adans. 

 Macerophyllum, Meusch. Maceris, Modeer. Macero- 

 phylla, Martini. Psilopus, Poli. 



Ex. C. imbricata, Broderij), pi. 113, fig. 1. Shell, C. 

 macerophylla, Chemnitz, fig. 1, a, 1, b. 



The shell of Chama consists of three layers; the outer or 

 coloured layer is laminated by oblique lines of growth, with 

 corrugations at right angles to the lamina? ; the foliaceous 

 spines contain reticulated tubuli ; the middle layer is opaque 

 white, and consists of ill-defined vertical prisms or corru- 

 gated structure ; the inner layer is transparent and mem- 

 branous, and penetrated by scattered, vertical tubuli. Up- 

 wards of forty species are known, from tropical seas. They 

 are found among coral-reefs in India, China, the West 

 Indies, the Canaries, and the Mediterranean. 



Species of Chama. 



aeruginosa, Lam. frondosa, Brod. 



appressa, Reeve. gryphoides, Linn. 



brassica, Reeve. imbricata, Brod. 



carditaeformis, Reeve. iostoma, Lam. 



cistula, Reeve. Janus, Reeve. 



cornuta, Chew. Japonica, Lam. 



corrugata, Brod. .Tubuli, Reeve. 



crenulata, Lam. laeiniata, Adams an, I Reeve. 



cristella, Lam. Lazarus, Linn. 



crocata, Lam. litnbula, Linn. 



(Ipcussata, Lam. lingua-felis, Reeve. 



exigua, Reeve. lobata, Brad. 



fimbriata, Reeve. macerophylla, Chem, 



florida, Lam. Pacifica, Brod. 



fragum, Reeve. Panamensis, Reeve. 



