How some ‘Roman Snails’ ended a Roman War

Peter Dance
In 1831, in the first edition of his Manual of the Land and Freshwater Shells of the British Islands, William Turton tells how some examples of what he thought may have been the Roman Snail, Helix pomatia, helped a Roman general capture a fort, thereby ending what became known as the Jugurthine War (111-105 BC). For the benefit of students of snail lore here is a condensed version of it, based on a modern translation of the Latin text Turton would have used, The Jugurthine War, written by the Roman historian Sallust (86-34 BC).
Towards the end of the 2nd century BC Rome was bogged down in a war with Jugurtha, ruler of a kingdom bounded by the river Mulucha (now Moulouya), situated in the north-eastern quarter of modern Morocco. In the year 106 the Roman general Gaius Marius had been besieging a small fort, strategically situated on a rocky hill, not far from the river. Sallust was either ignorant about African geography, or was careless about his facts, so the exact position of this fort is debatable, but it seems to have been in a mountainous district, possibly a short distance inland, near the border between modern Morocco and Algeria.
The fort had repeatedly resisted capture and Marius was almost at the point of admitting defeat when he received some promising news from a Ligurian mercenary who had been out of the Roman camp, searching for water. Having wandered to the vicinity of the fort furthest from the besiegers, the mercenary had seen some snails crawling among the rocks and decided to collect them. In his eagerness to collect more and more of them, presumably to eat, he had climbed almost to the top of the hill. Making use of the boughs of an oak tree at the top he had found he was able to survey the fort and its defences without being detected.
Encouraged by this news, Marius decided to mount an attack on the part of the fort the mercenary had just surveyed and sent some scouts to assess the chances of success. Receiving a positive report, he sent some armed men up the hill, guided by the mercenary. By attacking from this unexpected quarter they achieved a breakthrough, enabling Marius to make a successful assault. The capture of the fort ended the Jugurthine War.
The identity of the snails collected by the mercenary is uncertain. Helix pomatia, after all, is a Central European species and those he collected are unlikely to have been descended from specimens possibly imported for culinary purposes by the Romans. There are isolated instances of its occurrence well outside its natural range, however, including this one: ‘Specimens of H. pomatia, recently procured from Fez, are of extraordinary thickness as compared with forms from our own chalk downs of Kent and Surrey’ (A. H. Cooke, 1895, The Cambridge Natural History, Molluscs, p. 25). With good reason perhaps, another authority regarded these Moroccan shells as ‘probably not truly native’ (J. W. Taylor, 1910, Monograph of the Land & Freshwater Mollusca of the British Isles, Part 17, Vol. 3, p. 235). We cannot be sure of the identity of the snails collected by an unknown mercenary, but this in no way diminishes the interest of a story unique in the annals of conchology. This, surely, is the only instance of a longprotracted conflict being terminated because a man could not resist the temptation to collect snails!