The Slipper Shells. Cup-and-saucer Limpets 



reached. Unable to grow further in this direction, the shell 

 enlarges vertically, lifting the apex but keeping the base the 

 same seize. This adaptability to environment produces great 

 variation in form within the species. 



The female lays her yellow eggs in flat capsules which are 

 all attached to a common stalk as are the petals of a rose. Each 

 capsule is transparent and contains about a dozen eggs. The 

 shield-shaped shell protects the mother mollusk and her eggs. 

 The young hatch and are kept between the foot and the stone to 

 which the shell is attached until they acquire the neck frills of 

 hairs by which they are equipped for a free-swimming life. 



The Chinese Hat (C mamillaris, Brod.) is a low, white cone 

 with a central peak. It would require a doll mandarin to fit it. 

 Inside is the characteristic twisted deck of the genus. The cir- 

 cular rim is J inch in diameter. 



Habitat. — California northward. 



C. Candeana, d'Orb., occurs from Cape Hatteras to the 

 West Indies. 



THE HUNGARIAN CAPS 

 Genus CAPULUS, Montf. 



Shell conical, without internal plate or cup; apex spiral, 

 posterior; muscle scar horseshoe-shaped. 



A genus of few species, widely distributed. 



The Hungarian Cap ( C. Hungaricus, Linn. ) has no 

 tassel to pull its peak over to one side and downward, but it is 

 a perfect cap without it. The shell has fine, close, radiating lines 

 crossed by less frequent lines of growth. A horny epidermis, 

 often hairy, covers the outer surface, which is as white when 

 cleaned as the polished lining. The animal is held in the shell 

 by a strong muscular attachment. In British waters it is found 

 attached to shells and large rocks, especially near beds of oysters 

 and scallops, at depths varying from seven to eighty-five fathoms. 

 The mollusks are sedentary, shaping the shell margins to fit the 

 station, forming shallow excavations, sometimes depositing a 

 shelly floor. They feed on minute animal organisms and seaweed. 

 The -eggs are laid in membraneous cases which are attached in 

 a single tuft to the foot under the neck. 



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