226 vermetid^. 



Family YBRMETID^. 



Animal with rudimentary foot, head long, with two long 

 conical tentacles, and eyes at their outer bases ; proboscis re- 

 tractile ; on the sides of the buccal orifice are additional tentacles 

 or buccal appendages, also conical. Operculum circular, some- 

 times spiral. 



Shell tubular, attached ; sometimes regularly spiral when 

 young ; always irregular in its adult growth ; tube repeatedlj'' 

 partitioned off; aperture round. 



The Yermetidse are distinguished from the very similar shells 

 of the annelid genus Serpula by the presence of a spiral, nuclear 

 shell and of concave smooth interior septa. The shell of Serpula 

 is composed of two calcareous layers, that of Vermetidse of 

 three. 



Vermetus, Adanson. 



Shell irregularly spiral, or contorted tubular ; free, or attached 

 b}'^ one side like some of the annelids ; operculate. 



The following subgenera were considered distinct genera by 

 Morch : 



VERMICULUS, Lister. (Vermetus of authors, not Adanson.) 

 The shell is in its early stage regularly coiled like a Turritella, 

 and afterwards with the last whorl uncoiled, variously twisted, 

 or more or less straight and prolonged. There is apparently no 

 other distinction between the shells of Vermiculus and Burti- 

 nella, except that the latter are coiled in a broad, largely 

 umbilicated cone. 15 sp. Carboniferous — living. Tropical and 

 subtropical. V. lumbricalis, Linn. (Ixvii, 68). 



BURTiNELLA, Morch. (Morchia, Mayer.) Adult shell free, 

 young affixed, thick, widely conicallj^ elevated, trochiform or 

 planorboid, usually sinistral, rarely dextral ; whorls regularly 

 increasing in size, tubular within, angular without; the last 

 whorl dissolute, more or less prolonged, not constricted ; aperture 

 circular, margin continuous. Fossil, 15 sp. Oolitic, Cretaceous, 

 Tertiary; Europe, India. B. concava^ Stol. (Ixvii, 69, 10). 



STREPHOPOMA , Morch. Adult shell affixed , solitary or clustered ; 

 aperture slightly inflexed above, very obsoletely effused below. 

 Operculum arctispiral, furnished with long multifid setse. 

 Recent, 4 sp. *S'. rosea, Quoy (Ixvii, 11). The shells are gen- 

 erally very small, and usually so tender as to be very rarely 

 found fossil in a good state of preservation. Difficult to distin- 

 guish from Vermiculus. 



TUBULOSTIUM, Stoliczka. Shell free, planorboid to broadly 

 conical, aperture contracted, prolonged in a tube. 4 sp. 

 Jurassic ; Europe. Tertiary ; United States. Cretaceous ; 

 India. T. callosum, Stol. (Ixvii, 12, 13). 



siPHONiUM, Browne. (Stoa, M. de Serres.) Shell adherent. 



