118 GASTROCHiENID^. 



Distr. — 21 sp. Red Sea, Java, Australia, New Zealand ; in 

 sand. Fossil, 1 sp. (^4 ? i^eof/ria^ium, Hcening. Miocene ; Bor- 

 deaux.) 



Shell small, equilateral, cemented to the lower end of a shelly 

 tube, the umbones alone visible externally ; tube elongated, 

 closed below by a perforated disk with a minute central fissure ; 

 siphonal end plain or ornamented with ruffles. 



Animal elongated ; mantle closed, thickened and fringed with 

 filaments in front ; foot conical, anterior, opposed to a minute 

 slit in the mantle; palpi lanceolate; gills long, narrow, united 

 posteriorly, continued into and attached to the branchial siphon. 



WARNEA, Gray, 1858. The siphonal end of the tube fringed 

 with from one to several rows of ruffles. A. vaginiferum^ Lam. 

 (civ, 43). Red Sea. 



PENiciLLUS, Gray, 1858. Disk surrounded by a single fringe 

 of tubal! ; valves not surrounded by wavy depressions on the 

 surface of the tube. A. dichotomum, Chenu. 



CLEPSYDRA, Graj^, 1858. Fringe of the disk consisting of two 

 or three series of tubes ; valves not surrounded by wavy depres- 

 sions on the surface of the tube. A. strangulatum, Chenu. 



FOEGIA, Gray, 1840. Yalves not surrounded hy wavy depres- 

 sions ; coA^ered more or less by a sunken tubercle in front; disk 

 of the tube fringed. F. aggliUwans, Lam. 



ARYTENE, Gray, 1858. Like Foegia, but the disk not fringed. 

 A. Becluzianum, Chenu. 



HUMPHREYA, Gray, 1858. Tube attached by its base to a shell 

 or stone and much distorted in growth. H. Strangei, A. Ad. 

 (civ, 44). Australia. 



Subfamily GLAVAGELLINjE. 



Shell with the right valve only free, the left being imbedded 

 in the tube ; with or without radiated tubuli on the lower end of 

 the tube. 



Clavagella, Lamarck, 1801. 



Distr. — 6 sp. Mediterranean, Australia, Pacific ; 11 fathoms. 

 Fossil, 14 sp. Cretaceous — ; Britain, Sicily, Southern India. 



Shell oblong, valves flat, often irregular or rudimentary, the 

 left cemented to the side of the burrow, when adult, the right 

 always free; anterior muscular impression small, posterior large, 

 pallial line deepl}^ sinuated. Tube cylindrical, more or less 

 elongated, sometimes divided by a longitudinal partition; fur- 

 nished with a succession of siphonal fringes above, and termi- 

 nating below in a disk, with a minute central fissure, and bordered 

 with branching tubuli. 



Animal with the mantle closed in front, except a minute slit 

 for the foot, and furnished with tentacular processes ; palpi long 



