68 THE HAMILTON ASSOCIATION. 



of this generation, and while trifling omissions may be noted, we 



may find this definition fairly accurate of the following : 



Cones — Aperture efluse, longitudinal, without teeth. 



Cymea (Cowrie) — Aperture effuse, linear longitudinal, toothed on 



each side, except ovulum, inner lip smooth. 

 Murex — Aperture with small, straight canal. 

 Buccinum — Aperture with small canal leaning to the right. 

 Strombus — Aperture with small canal leaning to the left. 

 Trochus — Aperture contracted, somewhat square. 

 Turbo — Aperture contracted and orbicular. 

 Bulla — Aperture contracted a little and placed obliqilely. 

 Argonauta — ^With one cell, spiral, involute. 

 Nautilus — With many cells, passage of connection or syphuncle. 

 Halyotis — With a row of openings along surface. 

 Nerita — Under this head the early Conchologists included two dis- 

 tinct families —the Nerites (hoof shells), as commonly known, 

 and Naticas. The aperture of the former is contracted and 

 semi-orbicular ; in the latter it is globular, few whorled, spire 

 small, obtuse, lip acute ; a typical shell of each would readily 

 point out the difference. The foregoing are spirals. The 

 Univalves without a regular spire are : 

 Patella — Conic, aperture wide, basin-shaped. 

 Dentalium, or Tusk Shell — Slender, tapering, open at both ends. 

 Serpula (a worm, not a mollusc) — Shell hollow, often adhering to 



foreign bodies, serpentine. 

 Teredo — Shell thin, penetrating timber. 



I would advise any one who intends shell collecting, in the first 

 place to obtain a reliable work, such as "The Manual of the 

 MoUusca," by Woodward. Some changes have been made since an 

 edition was published in the 50's, but it contains a good deal of 

 information. That the plates are not colored is certainly a draw- 

 back. Its author found, if he carried out his original intention, it 

 must have made the work too expensive for general purposes. No 

 matter how accurate the outlines of a shell, the writer finds by 

 experience in many cases it is actually impossible to name a speci- 

 men correctly from an uncolored plate. Having lately received from 

 Ceylon a collection of Cofies and Coivries, he tried to name a few 

 from the cheap edition of " Tryon's Systematic Conchology," and 



