THE PLATES OF ANIMALS. 481 



Plate P. — 1. Area tetragona, with L a. its byssus. 2. Leda cauduta, 

 and 2. a. the expanded disk of its foot. 3. Leda pygmcea. 4. 

 Nucida nucleus. 5. Nucula tenuis. 6. Pectuncidics glycimeris, 

 Cd\\e^ pilosus on the plate. The drawing of 1. is by Mr. Alder ; 

 the others are from our own sketches after life. 



Plate Q. — 1. Ci/das rivicola. 2. Unio pictorum. 3. Anodonta cygnea, 

 with 3. a. its mantle-fringe. 4. Dreissena polymorpha, 4. a. and b. 

 details of its siphons, after sketches by Mr. J. de C. Sowerby. 5. 

 Mytilus edulis, and 5. a. part of its mantle-fringe. 6. Modiola 

 tidipa. 7. Crenella nigra (after a drawing by Mr. Alder). 



Plate R. — Lima hians (under Turton's name of X. tenera). 1. and 2. 

 different views of the animal fully expanded. 3. its foot. 4. one 

 of the cirrhi highly magnified. The beautiful driiwings from which 

 these figures were engraved, are among the many favours we owe to 

 the pencil and observation of our accomplished friend, Mr. Alder. 



Plate S. — 1. Pecten similis. 2. P. striatus, and 2. a. a portion of its 

 mantle highly magnified. 3. P. niveics, with 3. a. portion of its 

 mantle. 4. Avicida tarentina, drawn from a living Mediterranean 

 specimen (E, F.). 



Plate T. — 1. Ostrca cdulis (this beautiful figure was most kindly drawn 

 and engraved from the living animal by Mr. J. de Carle Sowerby). 

 2. Anomia ephippium. 3. Sphcenia Binghami, from a drawing 

 by Mr. Spence Bate. 



Plate U. — 1. Terebrattda caput-serpentis, 1. b. the under valve, and 

 1. c. the upper valve, laid open, from living specimens taken in 

 Loch Fyne, 2 Crania norvegica. 3. Hyalcea trispinosa, and 4. 

 Spirialis (after Souleyet), named Peracle on plate. 



Plate W. — 1. Panopcea norvegica, after a drawing from the living 

 British specimen by Mr. Richard Howse. 2. Poromya granidata, 

 after a sketch by Mr. M'Andrew. 3. AppendicvXaria, a slight 

 sketch from a British example. 



[Plates X, Y, Z, no such plates]. 



SERIES II. 

 GENERA OF GASTEROPODA AND CEPHALOPODA. 



Plate AA. — 1. Patella {Patina) pellucida. 2. Acnicea testiidinalis, 

 — 2. a. and b. one of the articulations of the tongue. 3. Pilidium 

 fulvmn, with 3. a. its head, showing the eyeless tentacles, and 3. b. 

 articulations of its tongue. 4. Propilidium ancyloide, with 4. a. 

 under side of its head, and 4. b. upper side of its head and position 



