Twait shad destruction. Conservation of this species is covered by Appendix III of the Bern Convention and Appendix II and V of the European Community Habitats Directive. The twait shad is a typical herring-type fish and much resembles the allis shad. It has no lateral line and the belly is more rounded than that of the sprat and Baltic herring. The gill cover is ridged and the caudal peduncle has large, plate-like scales. This fish is more colourful than the Baltic herring. The back is a bluish green colour and the head brownish with a golden tinge on the operculum. The flanks
Caudal luring often in juvenile snakes and is most prevalent in vipers and pitvipers, but it also occurs in boas, pythons, tropidophiids, colubrids, and elapids of the genus Acanthophis. Caudal luring has been used as an experimental paradigm to investigate stimulus control and visual perception in viperid snakes. It has been suggested that caudal luring was involved in the evolution of the rattlesnake rattle. Attempts have been made to test this hypothesis, however, the evidence is contentious. There have been dubious reports of caudal luring and concomitant speculations. Prey luring in general is confounded by false interpretation. The difficulty is that there