Humpback smooth-hound the lower ones. The teeth have a main pointed cusp and sometimes smaller subsidiary ones. The first dorsal fin is approximately triangular and the trailing edge is fringed with bare, dark-coloured collagen rods known as ceratotrichia. The pectoral fins are large and the pelvic fins moderately so. The caudal peduncle is short and the lower lobe of the tail fin is hardly curved in adults. The colour of this shark is plain grey or greyish-brown without any spots or barring. The humpback smooth-hound is found in the eastern Pacific Ocean off the coast of Peru and Chile, between 1°N and
Smooth scheme only if the morphism "X" → Spec "k" is smooth. A smooth scheme over a field is regular and hence normal. In particular, a smooth scheme over a field is reduced. Define a variety over a field "k" to be an integral separated scheme of finite type over "k". Then any smooth separated scheme of finite type over "k" is a finite disjoint union of smooth varieties over "k". For a smooth variety "X" over the complex numbers, the space "X"(C) of complex points of "X" is a complex manifold, using the classical (Euclidean) topology. Likewise, for a smooth variety