MALLEUS. 183 



leaving the nucleus or young shell behind, fills it up with calca- 

 reous matter to reside in the open extremity of the tube. Fig. 

 9, 10. Red Sea and Mauritius. 



MALACOTA. Schum. Otion. Leach. 



MALACOZOA. Bl. (MaXaicog, malacos, soft ; Zuov, zoon, animal.) 

 The type or general appellative in De Blainville's system, including 

 all molluscous animals, excepting those with multivalve shells. 



MALDANIA. Lam. The second family of the order Annelides 

 Sedentaria. The only genus of shells described in this family is 

 Dentalium, fig. 2, to which may be added Pharetrium, Konig. 

 fig. 3. It is doubtful however whether the latter do not belong 

 to an unknown genus of Pteropodous Mollusea. 



MALEA. Valenciennes. A genus composed of Dolium latilabrum, 

 Kiener, and other similar species. 



MALENTOZOA. Bl. (MaXctKog, malacos, soft ; zv, in, re/iva), 

 t em-no, cut ; Zwov, zoon, animal.) Or articulated mollusea. The 

 sub-type in De Blainville's system, comprehending those with 

 multivalve shells. 



MALLEACEA. Lam. A family belonging to the order of Conchi- 

 fera Monomyaria. Containing the following genera of irregular 

 pearly bivalves. 



1. Avicula. Hinge linear, simple, including Meleagrina. 



Fig. 163, 164. 



2. Pern a. Hinge with linear grooves, including Pulvinites. 



Fig. 166, 170. 



3. Gervillia. Shaped like Modiol a, with irregular grooves. 

 Fig. 162. 



4. Crenatula. Hinge with a series of pits. Fig. 168. 



5. Catillus. Like Perna, but more regular and convex. 



Fig. 167- 



6. Malleus. A triangular disc on the hinge, and two auricles. 

 Fig. 165. 



MALLEUS. Auct. {Malleus, a hammer.) Fam. Malleacea, 

 Lam. Margaritacea, Bl. — Descr. Equivalve, inequilateral, folia- 

 ceous, trilobate, undulated, irregular, attached by a byssus 



