CONANT HERA CONG JIOLOGY. 



the early part of the last century. Linncean class and 

 order Mdruecia Triandria, and natural order Amen- 

 tacccE. Generic character : male catkin cylindrical, 

 loosely imbricated; scales one-flowered; perianth of 

 two leaves ; corolla none ; filaments three, forked ; 

 anthers six, two valved. Female catkin ovate, thickly 

 imbricated ; scales one-flowered ; perianth of six 

 leaves ; styles two, like hairs ; nut one-seeded. The 

 leaves of this shrub are somewhat like those of fern, 

 it thrives on light sandy loam and moor-earth, and is 

 increased by layers. 



CONANTHERA (Ruiz and Pavon). A genus 

 of Chilian bulbs, belonging to Hexandria Monogynia, 

 and to the natural order Asphodeleae. Though not so 

 .splendid as others of the same class and character, 

 they are, however, interesting, and well worthy culti- 

 vation. Mr. Sweet observes of this genus " We 

 believe that this and some other nearly related ones, 

 would succeed better if out in a frame, on a warm 

 border, and be covered with a mat or other covering 

 in severe weather, than they do in pots." 



CONCHACEA. The eighth family of the third 

 order LameUibranchiata ; third class, Acephalnphora, 

 of De Blainville's system. It includes the genera 

 Cardium, Donax, Tcllina, Lucina, Cyclas, Cyprina, 

 Maclra, Erycina, Crasxatcllu, Venus, Venerirupis, Co- 

 rrtffinji/iaga, Clotho, Corbula, SpluBna, and Uxgulina. 

 The shells of this family are all of them bivalve, and 

 constitute a numerous portion of the most beautiful 

 molluscs. The general characteristics are : the shell 

 nearly always regular; perfectly closing; equivalve, 

 the summit recurved forward ; the hinge, dorsal and 

 complete, that is, with teeth and ligament, either 

 exterior or interior, short and swollen ; two distinct 

 muscular impressions. 



The mantle of the animal is closed in front, above, 

 and backwards, where it, is prolonged by two tubes 

 more or less long, extensible, either united or separate, 

 the abdomen constantly furnished with a f ; >ot, varyin; 

 somewhat in form, which is its onl v organ of locomotion. 

 All the animals of this family live concealed in the sand 

 or mud, at a greater or lesser depth, but they have 

 the faculty, and sometimes quit that situation; this is 

 effected by contracting the foot, which then acts as a 

 spring, arid they are propelled forward. Their 

 natural position is with the valves downwards when 

 concealed in the sand, and they then move forward 

 by slow degrees, in which operation the foot acts as a 

 lever to assist their march. Under the respective 

 names of the genera composing this family, the parti- 

 cular description of each species will be found. 



CONCHOLEPAS (Lamarck); PATELLA LEPAS 

 (Linnaeus). By many naturalists, this singular shell 

 has been considered a Patella, wilh which it was 

 classed by Linnaeus, from which it is most widely 

 different, by many characteristics, and particularly by 

 two distinctions, that of having a spire and being an 

 ojiercnlated shell. This error may, hi some degree, he 

 itr'.;<uinted for, by supposing that great man had only 

 nined an injured specimen of the shell, in which 

 the extremely small spire h;u! been worn off, that being 

 :iontly the case, the shell being generally much 

 wormed ; and, as he paid little or no attention to the 

 animals of shells, the opercnlurn, no doubt, was never 

 seen by him. Brugniere, observing the spire, classed 

 this shell with the Jinccinri, a fir more natural associ- 

 ation : this he did also on account of the slight notch 

 at the base ; but Sowerby has yet more properly con- 

 sidered it allied to the Purpura. From these consider- 



103 



able doubts exist in our mind of the propriety of 

 separating them. Lamarck classed this genus imme- 

 diately following that of Monvrcros, from having two 

 teeth at the base of the right side instead of one ; but 

 what he termed teeth, are no more than the continu- 

 ation of two external thickened ribs, which, being 

 flattened and broad, in no respect resemble the tooth 

 of the Moiioccms, which is a distinct sharp-pointed, 

 round, slightly convex point, and very differently 

 situated with regard to its position on the shell. 

 Lamarck's description of the shell is : shell oval, 

 inflated, half spiral, the summit inclined obliquely cm 

 the left side, columella flat, aperture very ample, 

 oblique, longitudinal, and with a slight notch at the 

 base ; two teeth at the lower part of the right margin. 

 To this we must add some other striking and constant 

 characters. The small spire is formed of three whorls, 

 the apex pointed ; it is nearly concealed by the very 

 widely expanded aperture, the left side of which is 

 greatly reflected, and forms a sharp angle above it ; 

 the right lip crenated at the base ; the exterior pre- 

 sents transverse grooves, or slightly formed ribs 

 diverging from the apex to the margin, and imbricated 

 with small scales and a horny operculum very closely 

 resembling that of the Bnccinum or Purpura. \\e 

 conclude the animal to be altogether unknown, not 

 having met with any description of it. Of this singular 

 genus the only species known is from the coast of 

 Peru, and is here figured. In beauty, this shell has little 



Concholepas Peruvianus, 



to recommend it, but, to the conchologist, it presents 

 much interest, as it is one of the well-defined instances 

 of the links of connexion existing throughout the 

 classes and genera of shells ; it illustrates that system 

 of gradation which, sooner or later, will complete one 

 general chain, and explain many phenomena, well 

 grounded in theory, but badly accounted for by 

 examples. In the system of De Blainville, this genus 

 is placed in the second class Paracephalophora ; h'rst 

 order Siphonobranchiata ; second family Entomasto- 

 nuita- it immediately follows the genus Purpura, and 

 precedes the genus Sirombus, but it is not unlikely that 

 it will ultimately form a division of the first, from 

 which we consider its separation as only temporary. 



CONCHOLOGY. Under this title, or that of 

 TESTACEOLOGY, naturalists have hitherto compre- 

 hended a systematic arrangement of shells, whether 

 marine, fluviatile, or terrestrial : it is the science by 

 means of which that branch of natural history is dis- 

 tributed into genera and species. The title concho- 

 lotry has, however, been somewhat misapplied, hav- 

 ing been used in a less extended sense than its etymo- 

 logical meaning implies ; since corichylion does not 

 express a shell only, but the molluscous animal, whose 

 body is altogether protected merely partially covered 



