328 GLOSSARY 



Page 



Globose, round and full, like a globe 5^ 



Glochidium, the young stage of a river-mussel. 301 

 Growth-striae, lines of growth on the shell . . . 265 

 Herbiverous, vegetable-eating, like the com- 

 mon snail 119 



Hinge-teeth, interlocking projections on cer- 

 tain bivalve shells 22 



Holdfast, the root-like parts of a seaweed. ... 101 

 Iridescent, showing the colors ot the rainbow. 224 

 Ligament, the elastic tissue at the hinge, which 



holds bivalve shells together 22 



Lunule, a heart-shaped depression 22 



MoLLusK, one of a great class of invertebrate 



animals 9 



Nacre, iridescent shell, like mother-of-pearl. . .232 

 NuLLiPORE, a kind of small, stony seaweed. . . .219 



NuDiBRANCH, a mollusk with naked gills 123 



Operculum, the door of a univalve shell 212 



Pallium, the skin, or mantle, of a mollusk. ... 21 

 Pelecypod, a bivalve mollusk, with ribbon-like 



gills, a lamellibranch 20 



Periostracum, the outer coating of a shell .... 23 



Peristome, the rim of a shell's aperture 287 



Reticulated, marked with net-work 129 



Rhinophores, certain sense-organs, probably of 



smell 125 



Serrations, ridges reseml:)ling saw-teeth 41 



Sinistral, opening on the left side 264 



Sinus, and inward curve, or ba}' 23 



Siphon, the breathing tube of a mollusk 21 



Species, a distinct type ot organisms 14 



