352 PHILINIDA, 
than at present estimated. Considerable additions, however, 
have been made to our knowledge on this subject by the re- 
searches of Kelaart in Ceylon and A. Adams in the Chinese seas. 
The shell-bearing genera flourished in the period when the sec- 
ondary strata were deposited. The living species are chiefly 
animal-feeders, preying on other shell-fish and on zoophytes. 
Orpver TECTIBRANCHIATA. 
Animal usually provided with a shell, both in the larval and 
adult state; branchiee covered by the shell or mantle. 
Faminy PHILINID 2. 
Shell usually present, sometimes wanting, internal, bulliform, 
but slightly spiral, usually not forming a single whorl; it is con- 
cealed under the lateral margins of the foat. 
Teeth, central none; lateral one or two, large, hooked. Ceph- 
alic disk oblong or subquadrate, without tentacular lobes; eyes 
none, or,if present, sessile on the head; mantle covering and 
concealing the shell; foot not produced posteriorly, the sides 
dilated, thick and fleshy ; gizzard armed with calcareous plates. 
PHILINE, Ascanias. 
Syn.—Bullea, Lam. Megistoma, Gabb. Utriculopsis, Sars. 
Distr.—20 sp. West Indies, Boreal Atlantic, Mediterranean, 
East Indies. Fossil, 7 sp. Eocene. P. aperta, Linn. ro 
14, 15). 
Shell internal, white, translucent, oval, slightly convoluted: 
spire e rudimentary. 
Animal pale, slug-like; mantle investing the shell; head 
oblong; eyeless ; foot broad ; lateral lobes large, but not 
enveloping ; tongue with two or four series of sickle-shaped 
uncini; gizzard with three longitudinal shelly plates. Egg- 
capsules ovate, in single series on a long spiral thread; fry 
with a ciliated head-veil and an operculated, spiral shell__-Lovgn. 
The animal is blind, like most creatures that seek their food 
by burrowing. They frequent mud-flats and slimy banks at the 
entrances of rivers, which they perforate near the surface, and 
probe with their flattened heads for the small bivalves which 
constitute their prey; these they seize and swallow entire, 
breaking their sheils by means of their. testaceous, muscular 
gizzards. 
CHELIDONURA, A. Adams. (Hirundella, Gray.) Shell con- 
cealed ; outer lip produced posteriorly into a spur; columellar 
border inflected. Animal with enveloping side-lobes; mantle 
with two appendages behind, like the lateral processes of Hyalia. 
P. hirundinaria, Quoy (Ixxxvii, 16; (7): 
