DIVISION XV. MAXLEACE.E. 



1. Crenatula. Lam. M. 



Sub-equivalved, flatten- 

 ed, foliated, somewhat ir- 

 regular. Fig. 69. 



GENERA. 



Hinge lateral, crena- 

 ted, callous. 



Ligament linear, mar- 

 ginal, received in the 

 hollows of the crenated 

 hinge ; no passage for a 

 byssus. (1) 



2. Pern a. Lam. M. 



Sub-equivalved, flatten- Hinge linear, margin- Ligament inserted he- 

 ed, irregular ; substance ai, composed of trans- tween the teeth : a pos- 

 scaly; beaks small, at one verse, parallel, sulciform terior sinus, gaping un- 

 end of the hinge. Fig. 72. teeth. der the extremity of the 



hinge, for the byssus. 



(2) 



3. I.noceramus. Sowerbj. 



Foss. 



Inequivalved, one beak Hinge straight, with Ligament like that of 

 curved inwards; substance teeth like the Perna. the Perna ; no passage 

 scaly. Fig. 74. 75. for a byssus. (3) 



4. Malleus. Lam. M. 



Sub-equivalved, rug- Hinge without teeth : Ligament almost ex- 

 ged, irregular, sub-lobed an elongated conical hoi- terior, inserted on the 

 at the base ; beaks small low, situated under the short area and slope of 

 and diverging. Fig. 73. beaks, traversing the each valve : with a bys- 



area of the ligament sus. (4) 



obliquely* 



every kind of dye, and is frequently woven, in Italy, into borders for shawls, etc, 

 The shells are found half buried in the sand. Foss. at Parma, Grignon. The 

 species found at the latter place, is distinct from all others; it is rather narrow, 

 three inches and a half long, and slightly rounded at its upper edge, Covered 

 within and without with mother-of-pearl, and longitudinally furrowed, without 

 offering any traces of scales or projection ; the striae of growth only forming some 

 faint wrinkles on the upper part, 



(1) They are very rare, little known, and principally found in warm climates, 

 enveloped in sponges. 



(2) Foss. in Blue Marl, Alum Shale, Virginia, Alsace, Vaches-Noires , Bur- 

 gundy. 



(3) Foss. in Blue Mart, Chalk, Clay. M. Brongniart wishes to separate the 

 Catillus (fig. 84) from the Inoceramus ; both are found in chalk, but in beds distant 

 from each other. An entire specimen of the Catillus, which certainly differs from 

 the Inoceramus, has not yet been discovered. Its hinges, from their fragments 

 (fig. 84. a. b.), resemble those of the Perna. 



(4) These shells are very rude in appearance ; the animal occupies but a small 

 space, which is covered with mother-of-pearl. 



