TUBICOUE. 



391 



siders them as the intermediate link between the Vertebrate and Annulosa, ob- 



a**- 



XCC§£y 



^•ytfn' 



serving upon the curious circum- 

 stance that these two subkingdoms, 

 so highly organized in the scale of 

 the creation, should be linked to- 

 gether by a group exhibiting such 

 great imperfections of structure. 

 This class has been greatly neg- 

 lected in this country. Dr. Johnston has, however, described various species (especially 

 in the Annals of Natural History, for February, 1840), and Mr. Mac Lcay, in the same 

 number,* has noticed several fossil species. It is, however, in France that the greatest 

 attention has been paid to them, especially by Savigny, Audouin, and Milne Edwards.] 



Fig". 193. — Svlli • monilmris, with one of its locomotive organs and setigerous 

 append ige attached thereto. 



THE FIRST ORDER OF ANXKLIDES. 



THE TUBICOL.E. 



Some species of this division form a homogeneous, calcareous tube, which probably results 



from their transudation, like the shells of the Mollusks, but to which the muscles do not adhere ; 



others construct tubes, by agglutinating grains of sand, fragments of shells, and particles of 



mud, which they join by means of a membrane, which likewise is doubtless transuded; lastly, 



then.- are some, the tubes of which are entirely membranous, or horny. 



To the first group belong 



Serpula, Linn., — 



The calcareous tubes of which invest, from their twisting about, fragments of stones, shells, and all sorts of 

 submarine matters. The truncation of these tubes is either round or angular, according to the species. 

 The animal within has its body composed of a great number of segments ; its fore-part widened 

 into a disk, furnished on each side with many bundles of Stiff bristles ; and on either side of its 

 mouth is a tuft of fan-like gills, in general vividly coloured. At the base of each tuft is a 

 fleshy filament ; and one of these, on the right or left side indifferently, is always prolonged and di- 

 lated at its extremity into a variously-formed disk, which serves for an operculum and mouth at the 

 entrance of the tube when the creature retires into it. 



The common species (.V. eontortuplieata, Ellis), lias a round and twisted tube three 

 lines in diameter. Its operculum is funnel-shaped, and its pills often of a fine red, or 

 varied with yellow, Violet, &c. This animal quickly fabricates its tube of mud, u^luti- 

 nating into it whatever small Objects lie around. 



There is another and smaller species on our coasts, with a club-Shaped operculum, 

 armed with two or three little points [B. vmniriiiiirix, Gineiin). In gilli ire sometimes 

 blue. Nothing is more beautiful to see than a proup of these Serpuhe when their s 

 are expanded. 



In other species, the operculum is fiat, and bristled with more numerous points. 

 These an- the Galeolaria, Laman k. 

 There is one in tie- Antilles (5 gigantea, Pallas), which is found among the Madre- 



rtuplicau, pons, ami the tube Of which is Often inclosed in their mass. Its ..nils roll up spirally 

 when they are withdrawn, and the operculum is armed with two little branching horns 



• Mr I : li niven the following jinnariaii di>tnbution of the clm« in the inemuir noticed ahove. 



ANN1 l.ll'A. 

 N"»»m\l (iaovr. 



f 



Marine animal*, having O 



provided with distinct feet. 

 AaaKHAS t Gaol r. 



f" I.uintn 

 IrltbuVl feel, or a di.tinrt ^ 



Do 



bead 



cidin* An I mm] I free, having adWtinct head, provided «lth tftt, or antenna*, or botk. 



I ma \niin.»U ledentary, ud baring no hi d ■ lib tynt or nnJ< 



briclna .. Animal* arllboml cjrt or antenna; ; body externally aether. >u» i»r I 

 tlnn diatincl. 

 rtina .. Anlmala tiqnntlCj without erei of inti 

 Indlillni t. 

 Animal . bninotwll i rnaaU/nnnV 



| artirulftllon 



