gas troche nidæ

pl. [Mod. Lat. gastro chan ( a ), and Lat. fom.pl. adj. suff. -idæ.] Zool.: A family of Mollusks, section Siphonida, and the sub-section, with the pallial line sinuated. The shell is equivalve and gaping, with thin edentulous valves united by a ligament, and sometimes when adult cemented in a shelly tube; adductors two; the animal elongated, truncated in front, produced behind into two very long contractile siphons. The species burrow in mud or stone. Chief genera Gastrochæna, Saxicava, Clavagella, and Aspergillum.