269 



NOTES 



On Foreign Jurassic species of the genus HOLECTYPUS, nearly allied to 

 British forms, but which have not yet been found in the English Oolites. 



HoLECTYPUS planus, Desor. Monogr. des Galerites, tab. 9, figs. 1 — 3. 



Test small, flat, pentagonal ; dorsal surface convex, base concave ; tubercles on the 

 upper surface small, about ten rows in the inter-ambulacra at the circumference, basal 

 tubercles much larger ; mouth small, central ; vent small, occupies only half the space 

 between the mouth and the border. 



Dimensions. — Height, seven twentieths of an inch ; transverse diameter, three quarters 

 of an inch. 



Formation. — Oxford Clay, Vaches-Noires, Normandy. 



Collections. — M. Michelin, ray Cabinet. Very rare. 



Holectypus Mandelslohi, Desor. Monogr. des Galerites, tab. 9, figs. 14 — 16. 



Test sub-conical; tubercles small on the upper surface, large at the base, arranged 

 in vertical and horizontal rows; mouth small; vent at the base nearly as wide as 

 the mouth ; miliary granulation abundant, and close-set. 



Dimensions. — Height, nine twentieths of an inch ; transverse diameter, eight tenths 

 of an inch. 



Formation. — Corallien inferieur (terrain a chailles), Albe Wurtembergeoise, Lusberg 

 (Canton du Soleure). "Argovien (avec Disaster granulosus) du 

 Randen de Birmansdorf, de Baden." Desor. 



Collections. — Count Mandelslohe, M. Gressly, M. Moesch. Mus. Bale, Mus. Neuchatel. 



