TEREDO. 123 



T. norvegica, but with smaller angular hiatus. Pallets 

 spade-shaped, the lower part of the disc being horny. 



10. PEDiciLLATA, f. 14, Quatrefages. — Valvse parvse ro- 

 tundse, ala depressa subexpansa. Tuba ad terminum conea- 

 merata. Palmulce biarticulatse. — The pallets are very peculiar, 

 being divided by a horny joint. 



11. GREGATA, f. 16, Laiiiarck. — Valvse angustissimge vix 

 alatse. Tuba contorta bulbiformis, ad terminum clausa, 

 rotunda. Palmulse ligoniformes, ad terminum concavae, 

 stipula brevissima. — This very curious Mollusc is found 

 living with the tubes coiled up together in the shells of 

 floating cocoa-nuts. The tubes are irregularly bulb-shaped 

 and closed at the end. The valves are extremely narrow. 



Species with horny, jointed stylets. ' 



12. BiPENNATA, f. 1 1 , Tuvton. — Valvse angustse promineute 

 alatse, hiatu postico ad alam acute angulato, intus carinato, 

 area antica angustissima. Styli cornei insequales angulatim 

 articulati. — The valves have much the aspect of N. megotara, 

 but the stylets are horny and angularly jointed. They are of 

 unequal length, one being a short palmet on a long stem, 

 the other a longer palmet on a shorter stem. 



13. CAEiNATA, f. 15, Gray. — Valvse ut in N. hlpennata 

 sed latiores. Styli elongati ; stipula elongatissima. — The 

 stylets are longer than in any other species, and the valves 

 are like those of N. bipenQiata, but a little broader. The 

 name refers to an overlapping inner edge of the posterior 

 wing, which is the same in several other species. 



14. PALMULATA, f. 4, Lamavck. — Valvse parvse breviter 

 alatse. Styli breves, angulatim pauciarticulati. — A small 

 species with narrow valves, the alse of which are roundly 

 projecting. Stylets short, six jointed at the broader end. 



15. Saulii, f. 18, Wright. — Valvse parvse rotundse an- 

 guste et rotunde alatse. Styli valde insequales, stipulis 

 brevissimis. Tuba solidiuscula, baud camerata. — A little 

 rounded species with scarcely prominent wings. The stylets 

 are both short, with very short stems ; one with the jointed 

 part shorter and more compressed than the other. 



