106 



CONCHO LOG Y. 



Genera and 



Species, 



Gen. XXXVIII. Isocarsia. 

 1. Cor. 



Gen. XXXIX. Terebratula. 

 1. Vitrea. 



Gen. XL. Nucula. 



1. Nuclea. 



2. Minuta. 



Gen. XLI. Arca. 



1. Lactea. 



2. Noa;. 



3. Rostrata. 



4. Tenuis. 



3. Fusca. 



Gen. XLII. Pecttjnctjlus. 

 1. Pilosus. 



DIVISION II. TOOTHLESS. 

 SECT. I. INEQUIVALVE. 



Gen. XLII I. Pecten. 



1 . Maximus. 



2. Jacoba?us. 



3. Opercularis. 



4. Varius. 



5. Lineatus. 



6. Distortus. 



Gen, XLIV. Ostrea. 

 1. Edulis. 



Gen. XLV. Anomia. 



1. Fphippium. 



2. Aculeata. 



7- Obsoletus. 



8. Glaber. 



9. LaRvis. 

 10. Similis. 

 1 1 Fragilis. 



12. Subauriculata. 



3. Undulata. 



4. Cymbiformis. 



SECT. II. EQUIVALVE. 



Gen. XLVI. Mytilus. 



1. Edulis. 



2. Ungulatus. 



3. Incurvatus. 



4. Pellucidus. 



5. Modiolus. 



6. Rugosus. 



7. Precisus. 



S. Crista-Galli. 



Gen. XLVII Pinna. 



1. Pectinata. 



2. Ingens. 



9- Discors. 



10. Discrepans. 



11. Cygneus. 



12. Anatinus. 



13. Avonensis. 



14. Plicatus. 



15. Decussatus. 



3. Muricata. 



ORDER III. MULTIVALVES. 

 DIVISION I. DENTATED. 



Gen. XLVIII. Pholas. 



1. Dactylus. 



2. Parvus. 



3. Crispatus. 



<Scn. XLIX. Teredo. 

 1. Navalis. 



4. Candidus. 



5. Striatus. 



DIVISION II. TOOTHLESS. 

 SECT. I. OPERCULATED. 



Species. 



Gen. L. Balanus. 



1. Communis. 



2. Balanoides. 



3. Punctatus. 



4. Rugosus. 



5. Clavatus. 



Gen. LI. Coronula. 

 1. Diadema. 



6. Tintinnabuluia. 



7. Costataa 



8. Conoides. 



9. Striatus. 

 10. Spongeosus. 



SECT. II. PEDUNCULATED. 

 Gen. LI I. Lepas. 



A. 



1. Anatifera. 



2. Anserifera. 



3. Sulcata. 



4. Faseicularis. 



5. Membranacea, 



B. 



6. Scalpellum. 



7. Polliceps. 



SECT. III. IMBRICATED. 

 Gen. LIII. Chiton. 



1. Marginatus. 



2. Lasvis. 



3. Ruber. 



4. Cinereus. 



5. Albus. 



6. Laevigatas. 



7. Faseicularis. 



8. Crinitus. 



shells. 



The formation of a collection of shells, is absolutely Formation 

 necessary to the successful prosecution of the science of a collec- 

 of Concholoffv. To accomplish this, much care and at- t,on °* 

 tention are requisite, shells must be sought lor m then 

 natural situations, and obtained, if possible, with the 

 animal alive. After the animal has remained dead in 

 the shell for any length of time, it loses its lustre and 

 transparency, and becomes less valuable, either as an 

 object of beauty or curiosity. Hence the collector must 

 explore the sea-coast, the land, and the fresh water, in 

 search of the testaceous animals which they support, 

 for the purpose of obtaining in a perfect state their cal- 

 careous coverings. 



The sea contains more species of shells than either 

 the land or the fresh waters, and presents to the concho- 

 logist an extensive field for observation. Many species 

 of marine shells frequent the sea shore, adhere to rocks, 

 stones, and sea-weed, or lodge in the clay or sand. 

 These are termed Littoral shells, and are seldom 

 found in deep water. The littoral shells are easily col- 

 lected at ebb tide. Those which burrow in the mud 

 or sand, may be detected by a small depression 

 which they leave on the surface, as they retire below 

 it. Other shells live in deeper water. To collect 

 these, the dredge must be employed ; and if the 

 shells be put into sea water after they are brought 

 up, the animals may afterwards be examined with ease. 

 Such collectors as have not the advantage of a dredge, 

 should examine the refuse of fishing boats, and traverse 

 the sea shore, and search the rejectamenta especially af- 

 ter a storm of wind. The roots of the larger Fitci, es- 

 pecially F. digitatus which grows sometimes in four or 

 five fathoms water, frequently contain a treasure of the 

 rarer shells. 



When vessels which have been long at sea come into 

 dock to be cleaned, their bottoms are often covered 



