stratulumn.

1797 R. Jameson Jrnl. in P. N. Wyse Jackson Four Cent. Geol. Trav. (2007) 40/1 I observed [a] considerable stratum of Limestone..divided into stratula with clay as is the case with the other stratums.

1798 R. Jackson Outl. Hist. & Cure Fever 95 This stratum has a singular aspect, owing to its being divided into a number of stratulæ, by means of interposed shistose clay.

a1803 J. Walker Ess. Nat. Hist. & Rural Econ. (1812) 386 This stone..is composed of stratula consisting of different sorts of agate matter.

1863 Rep. Devonshire Assoc. 1 37 The grains of sand are very small, and each stratulum is so thin as to be apparently one grain thick only.

1877 Proc. Dudley & Midl. Geol. & Sci. Soc. 3 116 The total thickness of the Rhaetic beds here amounts to 100 feet, consisting of 126 distinct layers or stratulae.

1908 Q. Jrnl. Geol. Soc. 64 198 The maximum angle at which stratula dip is of much interest as indicating the character of the material when it was deposited.

1947 Proc. Yorks. Geol. Soc. 27 10 If..the screw was turned first rapidly and then slowly, the sand became sorted into dark and light stratula dipping away from the screw.

1996 Neues Jahrbuch für Geologie und Paläontologie: Monatshefte 196 The Rzehakia Mb. [= member] consists of siltstone and massive or laminated fine sandstone, rarely with stratulum of claystone or coarse sandstone.