GASTEROPODA PECTINIBHANCHIATA. 379 



MuREX, Lin.(l) 



Comprises all those shells in which ihere is a salient and straight 

 cana](2). The animal of each subgenus is furnished with a pro- 

 boscis, long approximated tentacula on the external side of which 

 are the eyes, and with a horny operculum; the veil on the head is 

 wanting; and, the length of the siphon excepted, it otherwise re- 

 sembles that of the Buccina. Brugiere divides them into genera, 

 which have been since subdivided by Messrs Lamarck, and Monifort. 

 The 



MuREx, Brug. 



Includes all those which have a salient and straight canal, with vari- 

 ces across the whorls(3). 



Lamarck appropriates this name to those in which the varices are 

 not contiguous on two opposite lines. 



If their canal be long and slender, and the varices armed with 

 spines, they become the Mukex, properly so called, of Montfort(4). 



When, with this long canal, the varices are mere knobs, they form 

 the Brontis, Montf.(5) 



Some of them, which, with a moderate canal, have projecting 

 tubes that penetrate into the shell between spiny varices, constitute 

 the Typhis, Montf.(6) 



When, instead of spines, the varices are furnished with plicated 

 lamellae, slashed, or divided into branches, they are the Chicora- 

 CEA, Montf.(7) Their canal is long and moderate, and their foli- 

 aceous productions vary infinitely in figure and complication. 



When, with a moderate or short canal, the varices are mere knots, 



(1) This great genus forms the family Siphonostoma, Blainv. 



(2) To which Linnseus also added several Purpurse in which the canal is not 

 salient, and all the Cerithia in which it is recurved. 



(3) Varices are knobs with which tlie animal borders its mouth, at, each inter- 

 ruption in the growth of its shell. 



(4) Murex tribulus. List., 902, 2%Mur. brandarls, Li^t., 900, 20; Jfwn cor- 

 nidus, List., 901, 21; Mur. senegalensis, Gm., and the costatus of No. 86, Adans. 

 Seneg., VlII, 19. 



(5) Murex haustellum, List., 903, 23; Mur. caudatus. Martini, Conch., Ill, f. 

 1045, 1049; Mur. pyrum. 



(6) Murex tuhifer, Roissy, Brug., Journ. d'Hist. Nat., I, xi, 3: Montfort, 614 



(7) Murex ramosus. List., 946, 41, and all its varieties; Martini, 111, cv, ex, cxi; 

 Mur. Scorpio, Martini, cvi; Mur. saxatilis. Martini, cvii, cviii, and several 

 others not vet well characterized. 



