Bullia digitalis Bullia digitalis Bullia digitalis, the finger plough shell or plough snail, is a species of sea snail, a marine gastropod mollusk in the family Nassariidae, the Nassa mud snails or dog whelks. These dominant scavengers scent decaying animal matter from a considerable distance so that they converge from all directions to feed. Length: 60 mm Narrow, smooth shell with a long, pointed spire, usually light yellow or creamy, often tinged with violet or yellow. The large, oval foot is offwhite. The operculum has serrated margins. The ovate shell is elongated, subturreted, smooth and polished. It is of a reddish yellow
Derive (computer algebra system) calculators. Derive (computer algebra system) Derive was a computer algebra system, developed as a successor to muMATH by the Soft Warehouse in Honolulu, Hawaii, now owned by Texas Instruments. Derive was implemented in , also by Soft Warehouse. The first release was in 1988 for DOS. It was discontinued on June 29, 2007 in favor of the TI-Nspire CAS. The last and final version is Derive 6.1 for Windows. Since Derive required comparably little memory, it was suitable for use on older and smaller machines. It was available for the DOS and Windows platforms and was used also in TI