Dusky smooth-hound fishes is their ability to continually replace the teeth in their upper and lower jaws. Smooth dogfish differ from other sharks because of their 10 rows of flat, blunt teeth. The teeth in the upper and lower jaws are similar in size and are asymmetrical with rounded cusps. These teeth are used to crush and grind food, rather than bite it. Their unique dentition is important for their crustacean-based diet. In smooth dogfish, tooth replacement is related to body growth. They grow about 10 cm per every six rows of teeth replaced. That is an increase of 0.03 mm per
Slender smooth-hound may also receive secondary nutrition in the form of histotroph ("uterine milk") produced by the mother. When the embryo is long, it emerges from the capsule, which by that time has become translucent and gelatinous. Embryos long have well-developed external gill filaments. The external yolk sac is entirely absorbed when the embryo is long and close to being born. Males and females reach sexual maturity at approximately long. Harmless to humans and of no economic value, the slender smooth-hound is occasionally caught incidentally in bottom trawls and on bottom longlines. Much of its northern range lies in little-fished waters, and