PLATE 36, 37.. 
ANOMIT^. LIMESTONE AND SPAR. 
FIG. 1. 
CONCHYLIOLITHUS Anomites (trigonalis) xoi\m- 
do-trigonus, longitudinaliter sulcatus, sinu rotun- 
dato striato. S. p. 
A fossil shell. The original an Anomia. Perforate, with 
convex valves. Hinge straight, extended, patulous, divided 
between the beaks by a triangular foramen, or aperture. 
The general form, or outline of the shell, trigonal, or three- 
cornered, with the angles rounded crff ; its surface longitu- 
dinally furrowed and sinuated ; the furrows rounded ; their 
number varying from twenty to thirty ; the sinus continued, 
rounded, and extending the breadth of three or four fur- 
rows, hence striated like the other parts of the surface *. 
The beak of the larger valve is pointed, and generally 
much incurvated over the aperture; that of the smaller 
valve, short and obtuse. 
This is the most common species of Anomite we have in 
Derbyshire : it is found more or less throughout our lime- 
stone, frequently constituting beds of a very large extent. It 
forms the mass of stone represented in our 29th plate. The 
* This distinguishes trigonalis from triangularis and some other Ano~ 
mitre nearly allied in form, but in which the sinus is smooth, and may 
properly be considered as the central furrow, disproportionably larger than the 
lateral ones. 
