INDEX TO ILLUSTRATIONS. 
Plate I. 
1. Purpura crispata. Tlie 
p a r t s of a univalve 
shell. 
2. Tapes tenerrima. The in- 
terior of the left valve, 
showing the parts of the 
shell. 
Plate II. 
1. Pteronotus festivus. On 
rocks. 
2. Eanella Californica. 
3. Chrysodomus dims. Mos- 
sy rocks. 
4. Purpura saxicola. Rocks 
between tides. 
5. Pur p u r a canaliculata. 
Deeper water. 
6. Purpura crispata. Rocks. 
Plate III. 
1. Monoceros lapilloiaes. 
Surface of rocks. 
2. Chorus Belcheri. Very 
large. Southern. 
3. Monoceros engonatum. 
Rocks. 
4. Ampliissa corrugata. 
Dead, on beach. 
5. Amycla carinata. 
6. C e r o s t o m a foliatum. 
Rocks ; rare. 
Plate IV. 
1. Cerostoma Nuttallii. 
2. Nassa fossata. 
3. Nassa perpinguis. 
4. Nassa mendica. 
5. Nassa Cooperi. 
6. Olivella biplicata. Bur- 
rowing in sand. 
7. Olivella baetica. 
Plate V. 
1. Conus Californicus. 
2. Drillia torosa. Beach. 
3. Drillia penicillata. South- 
ern. 
4. Luponia spadicea. 
5. Trivia Californica. Beach. 
6. Erato vitellina, Beach. 
7. Erato columbella. 
Plate VI. 
1. Lunatia Lewisii. Sandy 
beaches. 
2. Ceritliidea sacrata. Mud 
of salt marshes. 
3. Bittium filosum. Sand, 
4. Scalaria crebricostata. 
5. Opalia borealis. 
6. Littor ina planaxis. ' 
Rocks. 
7. Littorina scutulata. 
Abundant on rocks. 
Plate VII. 
1. Lacuna uni f a sc i at a. 
Rocks and sand. 
2. Phachypoma gibberosum. 
Dead, on beach. 
3. Phasianella com pta. 
Sand. Very rich color- 
ing on shell. 
4. Pomaulax undosus. 
Ribbed operculum. 
5. Chlorostoma fun ebrale. 
Very abundant on rocks. 
6. Chlorostoma brunneum. 
Kelp. 
Plate VIII. 
1. Cholorostoma aureotinc- 
turn. Rocks. 
2. Calliostoma c o s t a t u in. 
Low water. 
