432 THE COMMON RAZOR-SHELL, 



Birmingham gun has taken the place of the Indian bow, the Sheffield hatchet the 

 place of the tomahawk, and the Witney blanket that of the original bear skin. 



About one hundred and seventy species of Venus-shells are known, spread through- 

 out all parts of the world, and ranging from low-water mark to a depth of one hundred 

 and forty fathoms. In the figure the animal is shown as it appears when crawling, the 

 slightly diverging ends of the double siphon appearing in front, and unequal in size, one 

 of the peculiarities of the genus. 



THE beautiful BRITISH CYTHEREA is seen in the foreground of the illustration, its 

 elongated siphons projecting towards the right like the tubes of a double-barrelled gun, 

 and their orifices surrounded with a fringe of tentacular appendages, and the thick 

 sturdy foot appearing behind. This genus is closely allied to the preceding, and is 

 therefore appropriately named Cytherea, that being one of the classical epithets applied 

 to Venus in consequence of her predilection for the island of Cytherea in the .^Egean 

 Sea. In this animal the two portions of the siphon do not diverge. 



IN the family of the Mactridae, or Trough-shells, the valves are of equal dimensions, 

 and rather triangular in shape. The animal has the two channels of the siphon united 

 as far as the extremity, and the foot is ample and strong. 



The common Trough-shell is a British species, and is found on many of our coasts, 

 always preferring those of a sandy nature, where it can hide itself by sinking just below 

 the surface. The foot is capable of considerable motion, and can be extended to some 

 length ; and when the movements are rapidly performed, it enables the creature to 

 jump about nearly as actively as the cockle. The Trough-shells are found in all parts 

 of the world, and in some coasts of our own islands are so plentiful that they are 

 gathered for the purpose of feeding pigs. The species which is usually employed for 

 this purpose is Macira subtrunedta, and, like the cockle, it is taken at low water. 

 Although so usually inhabiting the zones just below and above low-water mark, these 

 shells are sometimes found as low as thirty fathoms beneath the surface. 



THE very remarkable shell from which protrude two enormously long siphon tubes 

 is the SCROBICULARIA, an example of the family Tellinidae, all the members of which 

 are notable for the length and divergence of these tubes. 



These creatures are spread over the greater part of the globe, seldom inhabiting deep 

 water, and being fond of localities where the bed of the sea is of a sandy or muddy 

 nature, as they are able to bury themselves deeply in those substances, and to carry 

 on respiration, and obtain nutriment by means of the long siphon tubes. The larger 

 tube is that which is employed for the ingress of water, the shorter for its exit ; and 

 when the animal is at rest, it remains in an upright position in the sand or mud. The 

 orifices of the siphons are without fringes, and the tubes can be extended to five or 

 six times the length of the shell. The specific title of piperita, or peppery is given to 

 the animal on account of its peculiarly pungent flavor, which, however, does not 

 prevent it from being rather extensively consumed as an article of food in some 

 partsof the world. 



WE now come to the well-known Solenidae, or Razor-shells, so called on account of 

 their shape. 



These curious molluscs always live buried in the sand in an upright position, leaving 

 only an opening shaped like a keyhole, which corresponds with the two siphon tubes. 

 Those who are fond of examining the sand and rocks at low water will doubtlessly 

 have been startled and amused by little jets of water which spirt some few inches in 

 height, but never reappear. 



These are caused by the RAZOR-SHELL ; and if the locality whence the jet started be 

 watched, the little keyhole-like orifice will be seen. To catch the mollusc that emitted 

 the water is no easy task, but may be managed in two ways. The simplest but roughest 

 method is to take an iron rod hooked at the end, plunge it into the sand like a harpoon, 

 and pull it out smartly in an oblique direction, bringing with it the shell. This method, 



