PINGUICULA PIOPHILA. 



473 



any season of the year. It is a well-ascertained 

 fact that there are finer pine apples grown in 

 England than in any other country in the world. 

 In their native countries, although the flavour may 

 be equal, the fruit are inferior in size, and much less 

 juicy. 



The plant perpetuates itself by seed as well as by 

 viviparous progeny. Soon after' the fruit is ripe, the 

 old plant dies, but not till it has left a successor, on 

 the apex of the fruit, called a crown, and several 

 suckers from the lower part of the stem. These last 

 are mostly preferred as succession-plants, and are 

 rooted, placed in small pots, whence they are shifted 

 into larger and larger, until the plants attain such a 

 size as will enable them to show and ripen off a full- 

 sized fruit. Throughout the time of their nonage 

 they are kept in a strong moist heat, by which their 

 parts are srreatly amplified, and in twelve or fourteen 

 months are fit" to take their final station in the 

 fruiting-house. 



PINGUICULA (Linnaeus). A genus of pretty 

 herbaceous plants, natives of Europe and North 

 America. The flowers are diandrous/and the plants 

 belong to the natural order LcnlibularicE. They are 

 inhabitants of bogs and marshes, and known by the 

 name of butterwort in English lists. 



PINNOTHERES (Latreillc). A genus of small 

 crabs found upon our coasts, belonging to the sub- 

 order of Brachi/urous Decapods, and group named qua- 

 drilateral crabs by Latreille. These little crabs are 

 found during a portion of the year, especially in the 

 month of No/ember, in different bivalve shells, espe- 

 cially in those of the muscle. The shell of the females 

 is sub-orbicular, very slender and soft, whilst that of 

 the males is solid, globular, and somewhat pointed in 

 front. The legs are of moderate length, and the 

 claws straight ; the abdomen of the female is very 

 large, and covers the entire underside of the body. 

 They are ordinarily called pea-crabs, and it is within 

 the shells of the molluscous animals above-mentioned 

 that they both grow and breed. The ancients were 

 acquainted with these little crabs, for Aristotle 

 tells us that " there breed in some shells white and 

 very small crabs, the greatest numbers are found in 

 that species of muscle which have the shell protu- 

 berant ; next in that of the Pinna:, whose crab is 

 called Pinnotheres. They are also found in cockles 

 and oysters. These little animals never grow in any 

 sensible degree, and the fishermen imagine that they 

 are formed at the same time with the animal they 

 inhabit." He likewise supposed that their lives were 

 so dependent upon each other, that if the muscle 

 loses its little crab, both shortly afterwards perish. 

 " The pinna," according to Pliny, " is never found 

 without its companion, which is a little shrimp, in 

 some places a sr.iall crab, which bears it company in 

 order to partake of its food. The pinna, gaping wide 

 and showing her naked body to tempt the little fishes, 

 they soon make their approaches, and, when they find 

 they have full licence, grow so bold as to enter in 

 and fill it ; this, being seen by the guardian shrimp, 

 by a slight rap he gives the signal to the pinna, who, 

 therefore, shuts her shell, and suffocates whatsoever 

 it enclose?, giving a share of booty to her companion." 

 Oppian, still more absurdly, supposed that the Pin- 

 notheres, finding the shells of the bivalve open, throws 

 a small stone between them to prevent them from 

 closing, and so enables it to devour the inhabitant ; 

 whilst Hasselquist as ridiculously tells us, that the 



crab goes out to cater for the pinna, and when it 

 returns, cries out for the shell to be opened, which 

 the grateful inhabitant immediately complies with. In 

 more modern times, the people on the coasts where 

 these crabs are found attribute to their presence the 

 injurious qualities which some muscles possess. Say, 

 however, has described an American species under the 

 name of Pinnotheres ostreum, which is found in the 

 common oyster of that country, and which is stated 

 to be " excellent food ; and those who eat oysters, 

 seldom reject it when the fresh oyster is opened. In 

 considerable numbers the crabs are often collected 

 and served apart for the palates of the luxurious ;" 

 whence it is evident, that the opinion commonly en- 

 tertained that the injurious consequences which arise 

 occasionally from eating muscles must be owing to 

 other causes. For some of these observations we are 

 indebted to Mr. Thompson's valuable Memoir upon 

 this genus, in the third volume of the Entomological 

 Magazine, in which it is clearly proved that the con- 

 nexion of the Pinnotheres is parasitic, being never 

 found at large like some other aquatic animals which 

 occasionally make their way into shell-fish, since, in 

 sweeping on a bank of old muscles, " almost everv 

 shell will be found to contain one full-grown female, 

 some two, and others three, independent of young 

 ones ; and males, which occasionally occur in com- 

 mon with the females, while not a single individual is 

 to be seen." The type of the genus is the Cancer 

 jrisiini of Linna>us. There are several other species 

 described in the " Malacostraca Podopthalma Brit- 

 tannica," of Dr. Leach ; but this author has given the 

 younsr and the males as distinct species. 



PINTADINA. The name given by Lamarck to 

 one species of the genus Avicula, which Leach has 

 named Margarita. It is the shell known as the 

 mother-of-pearl oyster, and is described under the 

 article AVICOLA MARGARATIFERA, or pearl-bearing 

 Avicula, and under the leading head CONCHOLOGY. 

 Some mention is made of that highly-prized gem, the 

 produce of a diseased state of the animal, and the 

 source of an immense branch of commercial wealth 

 and national luxury in all parts of the globe, from 

 the very earliest period of history down to our 

 present times. We may here offer an apology for 

 not having fulfilled a pledge given that some account 

 of the pearl fishery would have been furnished our 

 readers, it having been considered unadvisablc to 

 introduce it in this division of the work. 



PIN US (Linnaeus). A well-known and useful 

 genus of forest trees, belonging to the truly natural 

 order Conifers. They are mostly natives of the 

 mountainous parts of the northern hemisphere, and 

 furnish the builder with the principal part of his 

 materials. There are above forty different sorts of 

 this genus in cultivation. Some of them are highly 

 ornamental, and all of them are well calculated for 

 forming sheltering screens, and for nursing trees of a 

 less hardy nature. They are raised from seeds, and 

 constitute a principal part of the business of British 

 nurserymen. 



PIOPHILA (Fallen; TYROPHAGA, Kirby). A 

 genus of dipterous insects, belonging to the family of 

 Muscidce, and having for its type the cheese-fly, Pio- 

 phila casci, an account of whose habits we have given 

 in our second volume, p. 9. The body in this genus 

 is small and polished ; the head sub-globose, without 

 any frontal projection, the antennae small with a single 

 bristle, and the legs moderately long and slender. In 



