Sastrugi breaking equipment—ripples and waves are often undercut and the surface is hard and unforgiving, with constant minor topographic changes between ridge and trough. The words "sastrugi" and "zastrugi" are Russian-language plurals; the singular is "sastruga" or "zastruga". The form "sastruga" started as the German-language transliteration of the Russian word заструга (plural: заструги). A Latin-type analogica singular "sastrugus" is used in various writings on exploration of the South Pole, including Robert Falcon Scott's expedition's diaries and Ernest Shackleton's "The Heart of the Antarctic". Under the action of steady wind, free snow particles accumulate and drift like the sand grains in barchan
Surface wave detection by animals to these by swimming 15 cm. The neuro-anatomical basis for this ability has not yet been identified. "A lineatus" and similar surface feeding fish (e.g. "Pantadon bucholzi") use a slightly modified lateral line organ called a neuromast to detect surface waves. "A lineatus" has 18 neuromasts (specialized vibration-sensitive lateral line organs) on the dorsal surface of the head of "A lineatus". These are organized into three groups by longitudinal position, and each group is bilaterally symmetric. The groups are, caudal to rostral: nasal/infraorbital (I), supraorbital (II), and supratemporal/post-orbital (III). Each neuromast is a cluster of hair-cell bundles arranged in a