PLEUROCERUS PLOVER. 



PLEUROCERUS (Cuvier). The animal of this 

 genus of mollusc is incompletely known, it appears 

 to have a probocitbrm head, two lateral tentacula, 

 subulated and pointed, the eyes externally placed at 

 base. The shell is oval or pyramidal, the aperture 

 oblong 1 , the external lip thin, the internal one at- 

 tached to the coluinella, which is smooth and twisted, 

 without an umbilicus, it has a horny or membranous 

 operculum. 



PLEUROTOMA (Lamarck ; MUREX, Lin- 

 naeus). Shells of this genus were classed with the 

 Muriccs by Linnaeus. Bruguiere in aftertimes con- 

 founded them with the genus Fi/$ns. Lamarck, in 

 the first instance, called such of them as had a 

 short canal Clavatulac, and the others Plmratomcc ; 

 but the very variable length of canal in the inter- 

 mediate species induced him to class the small 

 under the present genus, being guided only by the 

 notch on the upper part of the edge of the aperture. 

 With regard to the former arrangements, they cannot 

 properly be confounded with the Muriccs, as they 

 never possess the varices so remarkable in that genus; 

 and from the genus Fi/.titx they may readily be dis- 

 tinguished by possessing a long thin notch on the 

 right side of the aperture. These molluscs are either 

 turreted or fusiform, varying in length, terminated at 

 the base by a straight canal more or less lengthened ; 

 the right margin with a deep narrow notch or slit 

 near its upper part, the spiral whorls variously sculp- 

 tured as in the genus Ccrilhium, between which and 

 the genus TurbineUa they appear to form a natural 

 link. They possess a small horny operculum, and 

 many fossil species are known. They inhabit the 

 eastern and tropical sea?, and many of the species are 

 abundant in Java. 



PLEUROTUMARIUM. A fossil species of 

 mollusc established by De France, it appears inter- 

 mediate with the recent genera Turbo and Del- 

 phinula. 



PLICATULA(Lamarck; SPONDYLTJS, Linnscus). 

 The genus differs but little from the LimuEan ar- 

 rangement. Lamarck has, however, separated it for 

 the following reasons : the ligament is altogether in- 

 ternal as in the Pecten; it has the primary teeth of 

 the Spondylus,b\it without the ears or prolonged beak 

 which are so conspicuous in that genus. The Plica- 

 tides also possess the faculty of affixing themselves to 

 one another or various marine bodies grouped toge- 

 ther in clusters, as sometimes occurs in the genus 

 Spondylus; the valves are both of them closely inter- 

 locked and strongly plaited within and without ; the 

 summits are unequal and without external facet?. 

 Thev mostly inhabit the American seas, and several 

 fossil species are known. 



PLOIARIA (Scopoli). A curious genus of he- 

 mipterous insects, belonging to the family Cimiculfe, 

 and sub-family Reduviides, having the body very long 

 and slender, as well as the legs and antenna 1 , the 

 latter being elbowed at the extremity of the long 

 basal joint, the anterior legs are, however, short and 

 prehensile. The Cimc.i- r ft gab audits of Linnaeus is the 

 type of this genus, which is found in the larva and 

 pupa state in obscure and dirty situations. In the 

 imago state it is found in outhouses and in trees ; its 

 motion is very slow and irregular, and it balances 

 itself like a tipula without changing its place. Its 

 fore legs are not employed in walking, but are folded 

 three times beneath the head, the femur resting upon 

 the trochanter, and the tibia upon the femur, the 



477 



antennae seeming to make up for the deficiency by 

 being often brought into contact with the surface upon 

 which the insect is walking. The fore legs are there- 

 fore employed as instruments for seizing the prey ; 

 the rostrum is very short and curved, and the fore 

 legs being also short, are adapted for bringing the 

 food to the mouth. The pupa very nearly resembles 

 the perfect insect, but it is entirely covered with hairs 

 scattered over the body and legs. The perfect insect 

 is about one-fifth of an inch in length, of a whitish 

 colour with brown spots. 



PLOVER (Charadniis). A genus of Echassicrs, 

 or stilt birds, belonging to the pressirostral family, 

 and resembling the lapwings in their haunts and their 

 habits, but still distinct enough from them for being 

 considered as a separate genus. The principal gene- 

 ric characters are as follow : the bill shorter than the 

 head, slender, straight, compressed, and with the 

 nasal grooves extending two- thirds of the length, 

 which of course renders that portion of the upper 

 mandible weak and in part flexible ; the nostrils are 

 near the base of the bill, and toward the sides pierced 

 in, and partly covered by a membrane, which lines 

 the grooves to a considerable extent ; the tarsi are 

 long in some of the species, and of mean length in 

 others, and they are slender in all ; the toes are 

 three to the front, and none to the rear, united at the 

 base by a small membrane ; the first quill of the 

 wings is shorter than the second, which is the longest 

 in the wing. 



Plovers occur in many parts of the world, indeed 

 almost in all ; and they may be considered as birds 

 which range from place to place with the seasons, 

 although they are not decidedly migratory. In the 

 summer they are inland birds, dispersing in pairs for 

 the purpose of breeding. They breed on the mar- 

 gins of marshes and streams, generally in wild places, 

 but the eggs are deposited on the solid ground. In 

 some of the species, however, the eggs are placed on 

 the bare sand, and in others they are under cover of 

 aquatic plants ; but these differences appear to de- 

 pend fully as much on the country as on the birds. 

 After the broods are reared, the birds assemble in 

 considerable flocks, and descend from the breeding 

 places on the moors, first to the low grounds, and 

 ultimately to the beach, in countries where the winter 

 is severe. There are, however, great differences 

 among them in these as well as in other respects. 

 When they flock they are much esteemed as game, 

 and the more so probably that it is very difficult to 

 come within shot of them, as they always have sen- 

 tinels when the flock is feeding, which give the alarm 

 in a loud whistle upon the slightest appearance of 

 danger. When the alarm is given, the whole are on 

 the wing in an instant ; and, as they fly rapidly and 

 wheel and double adroitly with their pointed wings, 

 they soon get out of sight. Their food consists of 

 small ground animals, chiefly worms and mollusca ; 

 but it may reasonably be doubted whether they beat 

 he ground with their feer, in order to bring out the 

 worms, as is generally alleged of them. The fact is, 

 hat they are on the feeding grounds during that 

 weather and those times of the day when the worms 

 are out ; and by the time that the worms have begun 

 to sink deep in the ground in order to hybernate, as 

 they do in cold and upland places, the plovers are 

 ower down feeding upon mollusca. 



The common English name plover is a corruption 

 of the French pluvier or " rain bird," they being most 



