22 MUREX. 



in the warmer oceans, particularly about Panama. 

 The rock-shells, or Murines, usually are highly orna- 

 mented with frills, spines, or knobby varices, and are 

 sometimes gorgeously colored, particularly within the 

 aperture. Almost every house has a Murex among 

 its treasures, and a countless number of little children 

 have learned to notice and admire the beautiful shape 

 and color of one or more of these shells. 



Brilliant shells belong to warmer seas than this 

 part of the Pacific. The rare species which we are 

 now considering is of a dull-white color, marked with 

 brown stripes. It may easily be recognized by its 

 three sharp frills, its small oval aperture, and its 

 tubular canal. Its length is two or three inches. 



Another rare shell, sometimes found in southern 

 waters, is named Siphonalia Kellettii, Fbs., Si-fo- 

 na'-li-a Kel-let'-ti-i. My specimen is from Santa 

 Barbara ; it measures five inches in length, and thus 

 ranks among the largest of all our shells. It has a 

 regular, conical spire, three inches long, marked with 

 numerous rounded knobs. The aperture is elliptical 

 in shape, not very large, and the canal turns back- 

 ward. The shell is strong, heavy, white within, and 

 somewhat brownish without. 



Mitricidea incisa, Brod., Mu-ri-sid'-e-a in-si'-sa, 

 belongs to southern waters, and is not common. The 

 shell is marked by strong, rounded, transverse ridges, 

 which give the spire an appearance of being chopped 

 full of holes. Color, white, with cross-stripes of 

 brown ; length, an inch and a quarter. 



We have, in Fig. 3, the shell of another of the 

 southern species — one which loves warm water too 

 much to emigrate far to the north. Its name is 

 Pterouotus festivus, Hds., Ter-o-no'-tus fes-ti'-vus. 



